Pinus ponderosa

<h2 id="description">Description</h2>

Pinus ponderosa is a large <a href="/facts/Conifer/vDUgqxCx">coniferous</a> <a href="/facts/Pine/HvMa9uc1">pine</a> (<a href="/facts/Evergreen/bcLptUdV">evergreen</a>) tree. The <a href="/facts/Bark_(botany)/vdL49ec1">bark</a> helps distinguish it from other species. Mature to overmature individuals have yellow to orange-red bark in broad to very broad plates with black crevices.<a class="footnote-ref" id="fnref:12" href="#fn:12">12</a> Younger trees have blackish-brown bark,<a class="footnote-ref" id="fnref:13" href="#fn:13">13</a> referred to as "blackjacks" by early loggers. Ponderosa pine's five <a href="/facts/Variety_(botany)/r3qRdjVt">varieties</a>, as classified by some botanists, can be identified by their characteristically bright-green needles (contrasting with blue-green needles that distinguish <a href="/facts/Jeffrey_pine/UXSD7sTc">Jeffrey pine</a>). The Pacific variety has the longest—7+3⁄4 inches (19.8 centimetres)—and most flexible needles in plume-like <a href="/facts/Fascicle_(botany)/1YteJuoQ">fascicles</a> of three. The Columbia ponderosa pine has long—4+3⁄4–8 in (12–20.5 cm)—and relatively flexible needles in fascicles of three. The Rocky Mountains variety has shorter—3+1⁄2–5+3⁄4 in (9.2–14.4 cm)—and stout needles growing in scopulate (bushy, tuft-like) fascicles of two or three. The southwestern variety has 4+1⁄2–7+3⁄4 in (11.2–19.8 cm), stout needles in fascicles of three (averaging 2+3⁄4–3+1⁄2 in or 68.5–89 millimetres). The central High Plains variety is characterized by the fewest needles (1.4 per whorl, on average); stout, upright branches at narrow angles from the trunk; and long green needles—5+3⁄4–7 in (14.8–17.9 cm)—extending farthest along the branch, resembling a fox tail. Needles are widest, stoutest, and fewest (averaging 2+1⁄4–2+3⁄4 in or 56–71 mm) for the species.<a class="footnote-ref" id="fnref:14" href="#fn:14">14</a><a class="footnote-ref" id="fnref:15" href="#fn:15">15</a><a class="footnote-ref" id="fnref:16" href="#fn:16">16</a>
The egg-shaped cones, which are often found in great number under trees, are 3–5 in (8–13 cm) long. They are purple when first chewed off by squirrels, but become more brown and spherical as they dry.<a class="footnote-ref" id="fnref:17" href="#fn:17">17</a> Each scale has a sharp point.<a class="footnote-ref" id="fnref:18" href="#fn:18">18</a>
Sources differ on the scent of P. ponderosa. Some state that the bark smells of <a href="/facts/Turpentine/ME2Lgu0K">turpentine</a>, which could reflect the dominance of terpenes (alpha- and beta-pinenes, as well as delta-3-carene).<a class="footnote-ref" id="fnref:19" href="#fn:19">19</a> Others state that it has no distinctive scent,<a class="footnote-ref" id="fnref:20" href="#fn:20">20</a> while still others state that the bark smells like vanilla if sampled from a furrow.<a class="footnote-ref" id="fnref:21" href="#fn:21">21</a> Sources agree that the Jeffrey pine is more strongly scented than the ponderosa pine.<a class="footnote-ref" id="fnref:22" href="#fn:22">22</a><a class="footnote-ref" id="fnref:23" href="#fn:23">23</a> When carved into, <a href="/facts/Pitch_(resin)/GpdKnQMa">pitch</a>-filled stumps emit a scent of fresh pitch.<a class="footnote-ref" id="fnref:24" href="#fn:24">24</a>

<h3>Size</h3>
The <a href="/facts/National_Register_of_Big_Trees/TLk3AxrR">National Register of Big Trees</a> lists a ponderosa pine that is 235 ft (72 metres) tall and 27 ft (8.2 m) in circumference.<a class="footnote-ref" id="fnref:25" href="#fn:25">25</a> In January 2011, a Pacific ponderosa pine in the <a href="/facts/Rogue_River%25E2%2580%2593Siskiyou_National_Forest/M3MjrH8y">Rogue River–Siskiyou National Forest</a> in Oregon was measured with a laser to be 268 ft 4 in (81.79 m) high. The measurement was performed by <a href="/facts/Michael_Taylor_(forester)/B8nKAxj3">Michael Taylor</a> and Mario Vaden, a professional <a href="/facts/Arborist/AfvTAgfd">arborist</a> from <a href="/facts/Oregon/4Uq446Ko">Oregon</a>. The tree was climbed on October 13, 2011, by Ascending The Giants (a tree-climbing company in <a href="/facts/Portland%2c_Oregon/wwBx1Hrv">Portland, Oregon</a>) and directly measured with tape-line at 268 ft 3 in (81.77 m) high.<a class="footnote-ref" id="fnref:26" href="#fn:26">26</a><a class="footnote-ref" id="fnref:27" href="#fn:27">27</a> As of 2015, a <a href="/facts/Pinus_lambertiana/E75auBQk">Pinus lambertiana</a> specimen was measured at 273 ft 9+1⁄2 in (83.45 m),<a class="footnote-ref" id="fnref:28" href="#fn:28">28</a> which surpassed the ponderosa pine previously considered the world's tallest pine tree.<a class="footnote-ref" id="fnref:29" href="#fn:29">29</a>
<h2 id="taxonomy">Taxonomy</h2>
Pinus ponderosa was <a href="/facts/Author_citation_(botany)/EtBycMfH">scientifically described</a> and named by <a href="/facts/Charles_Lawson_(nurseryman)/QhlkJoHI">Charles Lawson</a> working from information provided by <a href="/facts/David_Douglas_(botanist)/D8cQHMTS">David Douglas</a> in 1836.<a class="footnote-ref" id="fnref:30" href="#fn:30">30</a><a class="footnote-ref" id="fnref:31" href="#fn:31">31</a>
The taxonomy of the ponderosa pine is heavily disputed by botanists and foresters. As recently as 2013 Robert Z. Callaham writing a research paper for the US Forest Service claimed that it is a single species from the Rocky Mountains to the Pacific coast divided into five <a href="/facts/Subspecies/4L9jFacF">subspecies</a>.<a class="footnote-ref" id="fnref:32" href="#fn:32">32</a><a class="footnote-ref" id="fnref:33" href="#fn:33">33</a> However, the USDA <a href="/facts/Natural_Resources_Conservation_Service/Fluo577b">Natural Resources Conservation Service</a> PLANTS database (PLANTS) lists these as <a href="/facts/Variety_(botany)/r3qRdjVt">varieties</a> as of 2025<a href="https://en.wikipedia.org/w/index.php?title=Pinus_ponderosa&action=edit">[update]</a>.<a class="footnote-ref" id="fnref:34" href="#fn:34">34</a> In the World Plants database maintained by Michael Hassler only three varieties are recognized, one described in 2024.<a class="footnote-ref" id="fnref:35" href="#fn:35">35</a> On the other hand the <a href="/facts/World_Flora_Online/fqY9CS1x">World Flora Online</a> (WFO) lists just two varieties.<a class="footnote-ref" id="fnref:36" href="#fn:36">36</a> While <a href="/facts/Plants_of_the_World_Online/2m4CsqY0">Plants of the World Online</a> (POWO) lists four varieties, but separates out two other <a href="/facts/Taxa/caQC1e87">taxa</a> recognized as varieties as species.<a class="footnote-ref" id="fnref:37" href="#fn:37">37</a><a class="footnote-ref" id="fnref:38" href="#fn:38">38</a><a class="footnote-ref" id="fnref:39" href="#fn:39">39</a> Similarly to POWO Christopher J. Earle writes in the Gymnosperm Database that the ponderosa pine has three subspecies and recognizes two taxa as species.<a class="footnote-ref" id="fnref:40" href="#fn:40">40</a> In the <a href="/facts/Flora_of_North_America/w0BKpUP2">Flora of North America</a> (FNA) three varieties are recognized.<a class="footnote-ref" id="fnref:41" href="#fn:41">41</a>

<h3>Subspecies and varieties</h3>
<ul><li>Pinus ponderosa var. arizonica (<a href="/facts/Engelm./XD9hSXxQ">Engelm.</a>) <a href="/facts/George_R._Shaw/DNt3Wbjk">Shaw</a></li></ul>
This variety is listed in the Flora of North America,<a class="footnote-ref" id="fnref:42" href="#fn:42">42</a> but is generally recognized as the species <a href="/facts/Pinus_arizonica/NHd17jU3">Pinus arizonica</a>.<a class="footnote-ref" id="fnref:43" href="#fn:43">43</a><a class="footnote-ref" id="fnref:44" href="#fn:44">44</a>
<ul><li>Pinus ponderosa var. benthamiana (<a href="/facts/Hartw./qPWhJGJo">Hartw.</a>) <a href="/facts/George_Vasey_(botanist)/xfMzYljc">Vasey</a></li></ul>
The <a href="/facts/Olympic_Peninsula/nW8FJa47">Olympic Peninsula</a> in Washington State, Oregon west of the Cascade Range, the whole of California, and far north eastern Nevada. This variety is recognized by PLANTS as the correct name for subspecies critchfieldiana.<a class="footnote-ref" id="fnref:45" href="#fn:45">45</a> It is also listed as accepted by POWO,<a class="footnote-ref" id="fnref:46" href="#fn:46">46</a> but is considered a synonym of var. ponderosa by both World Plants and WFO.<a class="footnote-ref" id="fnref:47" href="#fn:47">47</a><a class="footnote-ref" id="fnref:48" href="#fn:48">48</a>
<ul><li>Pinus ponderosa var. brachyptera <a href="/facts/George_Engelmann/XD9hSXxQ">Engelm.</a> – southwestern ponderosa pine<a class="footnote-ref" id="fnref:49" href="#fn:49">49</a></li></ul>
Four corners transition zone, including southern Colorado, southern Utah, northern and central New Mexico and Arizona, westernmost Texas, and a single disjunct population in the far northwestern Oklahoma panhandle.<a class="footnote-ref" id="fnref:50" href="#fn:50">50</a> The <a href="/facts/Gila_Wilderness/Hh1rduES">Gila Wilderness</a> contains one of the world's largest and healthiest forests.<a class="footnote-ref" id="fnref:51" href="#fn:51">51</a> Hot with bimodal monsoonal rainfall; wet winters and summers contrast with dry springs and falls; mild winters. This variety is recognized in PLANTS,<a class="footnote-ref" id="fnref:52" href="#fn:52">52</a> but is considered a synonym of var. scopulorum by WFO and FNA,<a class="footnote-ref" id="fnref:53" href="#fn:53">53</a><a class="footnote-ref" id="fnref:54" href="#fn:54">54</a> of var. ponderosa by World Plants,<a class="footnote-ref" id="fnref:55" href="#fn:55">55</a> and as the species Pinus brachyptera by POWO.<a class="footnote-ref" id="fnref:56" href="#fn:56">56</a>
<ul><li>Pinus ponderosa var. pacifica J.R. Haller & Vivrette – Pacific ponderosa pine</li></ul>
100–2,700 m (330–8,860 ft) on coastal-draining slopes of major mountain ranges in California, and in southwestern Oregon, Washington.<a class="footnote-ref" id="fnref:57" href="#fn:57">57</a> This variety was described in 2011 by John Robert Haller and Nancy J. Vivrette.<a class="footnote-ref" id="fnref:58" href="#fn:58">58</a> It is accepted by POWO, but is considered a synonym of var. ponderosa by WFO and World Plants.<a class="footnote-ref" id="fnref:59" href="#fn:59">59</a><a class="footnote-ref" id="fnref:60" href="#fn:60">60</a>
<ul><li>Pinus ponderosa var. ponderosa <a href="/facts/David_Douglas_(botanist)/D8cQHMTS">Douglas</a> ex C. Lawson – Columbia ponderosa pine, North plateau ponderosa pine<a class="footnote-ref" id="fnref:61" href="#fn:61">61</a></li></ul>
This is the <a href="/facts/Autonym_(botany)/QuydfKJy">autonymic</a> variety of the species.<a class="footnote-ref" id="fnref:62" href="#fn:62">62</a> Its range depends upon how many varieties are combined with it, if combined with var. pacifica and/or var. benthamiana as in FNA it extends further south into California, but not inland to Montana.<a class="footnote-ref" id="fnref:63" href="#fn:63">63</a> The definition of the variety used by <a href="/facts/Jepson_Herbarium/Ezlv77Aq">Jepson Herbarium</a> similarly includes southeast British Columbia, eastern Washington State and Oregon east of the Cascade Range, northeastern California, and northwestern Nevada, but additionally indludes Idaho and west of the Helena, Montana. This area has cool, relatively moist summers; very cold, snowy winters (except in the very hot and very dry summers of central Oregon, most notably near Bend, which also has very cold and generally dry winters).<a class="footnote-ref" id="fnref:64" href="#fn:64">64</a><a class="footnote-ref" id="fnref:65" href="#fn:65">65</a>
<ul><li>Pinus ponderosa var. scopulorum (<a href="/facts/George_Engelmann/XD9hSXxQ">Engelm.</a> in S.Watson) E. Murray, Kalmia 12:23, 1982 – Rocky Mountain ponderosa pine<a class="footnote-ref" id="fnref:66" href="#fn:66">66</a></li></ul>
Variety scopulorum is recognized by WFO,<a class="footnote-ref" id="fnref:67" href="#fn:67">67</a> PLANTS,<a class="footnote-ref" id="fnref:68" href="#fn:68">68</a> World Plants,<a class="footnote-ref" id="fnref:69" href="#fn:69">69</a> and the FNA.<a class="footnote-ref" id="fnref:70" href="#fn:70">70</a> It is considered a species by POWO.<a class="footnote-ref" id="fnref:71" href="#fn:71">71</a> The distribution of this taxa is different depending on its definition, for example being very widespread in the FNA and much more restricted in POWO.<a class="footnote-ref" id="fnref:72" href="#fn:72">72</a><a class="footnote-ref" id="fnref:73" href="#fn:73">73</a>
<ul><li><a href="/facts/Pinus_ponderosa_var._washoensis/fdBhITCt">Pinus ponderosa var. washoensis</a> (H. Mason & Stockw.) J.R. Haller & Vivrette – Washoe pine<a class="footnote-ref" id="fnref:74" href="#fn:74">74</a></li></ul>
Predominantly in northeastern California, and into Nevada and Oregon, at 2,000–3,000 m (6,600–9,800 ft), upper mixed-conifer to lower subalpine habitats.<a class="footnote-ref" id="fnref:75" href="#fn:75">75</a><a class="footnote-ref" id="fnref:76" href="#fn:76">76</a>
Distributions of the subspecies in the United States are shown in shadow on the map. Distribution of ponderosa pine is from Critchfield and Little.<a class="footnote-ref" id="fnref:77" href="#fn:77">77</a> The closely related five-needled <a href="/facts/Arizona_pine/NHd17jU3">Arizona pine</a> (Pinus arizonica) extends southward into Mexico.
Before the distinctions between the North Plateau and Pacific races were fully documented, most botanists assumed that ponderosa pines in both areas were the same. In 1948, when a botanist and a geneticist from California found a distinct tree on Mt. Rose in western Nevada with some marked differences from the ponderosa pine they knew in California, they described it as a new species, Washoe pine Pinus washoensis. Subsequent research determined this to be one of the southernmost outliers of the typical North Plateau race of ponderosa pine.<a class="footnote-ref" id="fnref:78" href="#fn:78">78</a>: 30–31 <a class="footnote-ref" id="fnref:79" href="#fn:79">79</a><a class="footnote-ref" id="fnref:80" href="#fn:80">80</a><a class="footnote-ref" id="fnref:81" href="#fn:81">81</a> Its current classification is Pinus ponderosa var. washoensis.<a class="footnote-ref" id="fnref:82" href="#fn:82">82</a><a class="footnote-ref" id="fnref:83" href="#fn:83">83</a><a class="footnote-ref" id="fnref:84" href="#fn:84">84</a>
An additional variety, tentatively named <a href="/facts/Pinus_ponderosa_var._willamettensis/HGUzXbTH">P. p. var. willamettensis</a>, found in the <a href="/facts/Willamette_Valley/pU7cTNwN">Willamette Valley</a> in western Oregon, is rare.<a class="footnote-ref" id="fnref:85" href="#fn:85">85</a> This is likely just one of the many islands of Pacific subspecies of ponderosa pine occurring in the Willamette Valley and extending north to the southeast end of Puget Sound in Washington.

<h3>Distinguishing subspecies</h3>
The subspecies of P. ponderosa can be distinguished by measurements along several dimensions:<a class="footnote-ref" id="fnref:86" href="#fn:86">86</a>: 23–24 <a class="footnote-ref" id="fnref:87" href="#fn:87">87</a>: 17 

<table><tbody><tr><th> Common name</th><th> Pacific </th><th> Columbia </th><th> Rocky Mountains </th><th> Southwestern </th><th> Central High Plains </th></tr><tr><th> Scientific name</th><th> P. p. critchfieldiana </th><th> P. p. ponderosa </th><th> P. p. scopulorum </th><th> P. p. brachyptera </th><th> P. p. readiana </th></tr><tr><td> Years needles remain green</td><td> 3.9±0.25, N=30 </td><td> 4.7±0.14, N=50 </td><td> 5.7±0.28, N=23 </td><td> 4.3±0.18, N=24 </td><td> 4.7±0.18, N=5 </td></tr><tr><td> Foliage length on branch (cm)</td><td> 25.1±2.4, N=30 </td><td> 26.2±2.2, N=50 </td><td> 21.1±1.7, N=23 </td><td> 21.8±2.7, N=24 </td><td> 42.2±6.7, N=5 </td></tr><tr><td> Needle length (cm)</td><td> 19.8±0.44, N=30 </td><td> 16.8±0.29, N=48 </td><td> 11.2±0.27, N=23 </td><td> 14.7±0.45, N=24 </td><td> 15.6±0.57, N=5 </td></tr><tr><td> Needles per fascicle</td><td> 3.0±0.00, N=30 </td><td> 3.0±0.00, N=48 </td><td> 2.6±0.06, N=23 </td><td> 3.0±0.03, N=24 </td><td> 2.4±0.11, N=5 </td></tr><tr><td> Needle thickness</td><td> 45.9±0.49, N=30 </td><td> 47.8±0.51, N=48 </td><td> 46.4±0.68, N=23 </td><td> 44.8±0.87, N=24 </td><td> 49.7±0.61, N=5 </td></tr><tr><td> Branches per whorl</td><td> 4.4±0.13, N=30 </td><td> 3.7±0.11, N=50 </td><td> 3.0±0.17, N=23 </td><td> 3.4±0.25, N=23 </td><td> 2.3±0.11, N=5 </td></tr><tr><td> Branch angle (° from vertical)</td><td> 56±1.8, N=30 </td><td> 51±1.7, N=50 </td><td> 50±2.3, N=23 </td><td> 48±3.1, N=24 </td><td> 36±1.9, N=5 </td></tr><tr><td> Seed cones length (mm)</td><td> 101.4±2.48, N=25 </td><td> 88.7±1.24, N=36 </td><td> 70.7±2.20, N=22 </td><td> 74.9±2.51, N=20 </td><td> 71.1±2.46, N=5 </td></tr><tr><td> Seed cones width (mm)</td><td> 77.1±1.35, N=25 </td><td> 71.6±0.73, N=36 </td><td> 61.5±1.08, N=22 </td><td> 62.6±1.77, N=20 </td><td> 63.3±2.18, N=5 </td></tr><tr><td> Seed cone form W/L</td><td> 0.80±0.03, N=25 </td><td> 0.84±0.03, N=36 </td><td> 0.90±0.02, N=22 </td><td> 0.86±0.02, N=20 </td><td> 0.90±0.03, N=5 </td></tr><tr><td> Seed length (mm)</td><td> 7.5±0.08, N=23 </td><td> 7.6±0.16, N=14 </td><td> 6.3±0.09, N=17 </td><td> 6.4±0.18, N=16 </td><td> 7.0±0.12, N=5 </td></tr><tr><td> Seed width (mm)</td><td> 4.9±0.05, N=23 </td><td> 4.9±0.08, N=14 </td><td> 4.1±0.05, N=17 </td><td> 4.3±0.09, N=16 </td><td> 4.5±0.10, N=5 </td></tr><tr><td> Seed + wing length (mm)</td><td> 32.3±0.58, N=23 </td><td> 24.8±0.62, N=14 </td><td> 22.9±0.63, N=17 </td><td> 23.3±0.68, N=15 </td><td> 23.1±0.78, N=5 </td></tr><tr><td> Mature cone color<a class="footnote-ref" id="fnref:88" href="#fn:88">88</a></td><td> apple green to yellow green</td><td> green & red-brown to dark purple</td><td> green & red-brown to dark purple</td><td> </td><td> green & red-brown to dark purple</td></tr></tbody></table>
Notes
Names of taxa and transition zones are on the map.
Numbers in columns were derived from multiple measurements of samples taken from 10 (infrequently fewer) trees on a varying number of geographically dispersed plots.
Numbers in each cell show calculated mean ± standard error and number of plots.

<h2 id="distribution">Distribution</h2>

Pinus ponderosa is a dominant tree in the <a href="/facts/A._W._Kuchler/Rwz6INvL">Kuchler</a> plant association, the <a href="/facts/Ponderosa_shrub_forest/AwkoQCuj">ponderosa shrub forest</a>. Like most western pines, the ponderosa is generally associated with mountainous topography. However, it is found on banks of the <a href="/facts/Niobrara_River/H3HH2LpQ">Niobrara River</a> in Nebraska. Scattered stands occur in the <a href="/facts/Willamette_Valley/pU7cTNwN">Willamette Valley</a> of Oregon and in the <a href="/facts/Okanagan_Valley/JB93RuEM">Okanagan Valley</a> and <a href="/facts/Puget_Sound/A7TgLsHA">Puget Sound</a> areas of Washington. Stands occur throughout low level valleys in British Columbia reaching as far north as the Thompson, Fraser and Columbia watersheds. In its Northern limits, it only grows below 4,300 feet (1,300 m) elevation, but is most common below 2,600 feet (800 m). Ponderosa covers 1 million acres (4,000 km2), or 80%,<a class="footnote-ref" id="fnref:89" href="#fn:89">89</a> of the <a href="/facts/Black_Hills/DQzybXIX">Black Hills</a> of <a href="/facts/South_Dakota/R51Fbf1t">South Dakota</a>. It is found on foothills and mid-height peaks of the northern, central, and southern <a href="/facts/Rocky_Mountains/rDc3cU0E">Rocky Mountains</a>, in the <a href="/facts/Cascade_Range/v7n1chTV">Cascade Range</a>, in the <a href="/facts/Sierra_Nevada_(U.S.)/tKcI8PeH">Sierra Nevada</a>, and in the maritime-influenced <a href="/facts/Coast_Range_(EPA_ecoregion)/cVj5eGmR">Coast Range</a>. In <a href="/facts/Arizona/6ayM3swJ">Arizona</a>, it predominates on the <a href="/facts/Mogollon_Rim/gzM7d4YJ">Mogollon Rim</a> and is scattered on the <a href="/facts/Mogollon_Plateau/ngzv7aIh">Mogollon Plateau</a> and on mid-height peaks (6,000 to 9,300 feet; 1,800 to 2,800 m) in Arizona and <a href="/facts/New_Mexico/wosJCGaW">New Mexico</a>.<a class="footnote-ref" id="fnref:90" href="#fn:90">90</a><a class="footnote-ref" id="fnref:91" href="#fn:91">91</a> Arizona pine (P. arizonica), found primarily in the mountains of extreme southwestern New Mexico, southeastern Arizona, and northern Mexico and sometimes classified as a variety of ponderosa pine, is presently recognized as a separate species.<a class="footnote-ref" id="fnref:92" href="#fn:92">92</a> Ponderosa pine are also found in the <a href="/facts/Chisos_Mountains/NcVUIR63">Chisos</a>, <a href="/facts/Davis_Mountains/bKRaSSI6">Davis</a>, and <a href="/facts/Guadalupe_Mountains/5Uwvl0RV">Guadalupe Mountains</a> of <a href="/facts/Texas/B987WHF0">Texas</a>, at elevations between 4,000 and 8,000 feet (1,200 and 2,400 m).<a class="footnote-ref" id="fnref:93" href="#fn:93">93</a>

<h2 id="ecology">Ecology</h2>
Main article: <a href="/facts/Ponderosa_pine_forest/02NSNNPQ">Ponderosa pine forest</a>

The <a href="/facts/Fire_cycle/zABpjqff">fire cycle</a> for ponderosa pine is 5 to 10 years, in which a natural ignition sparks a low-intensity fire.<a class="footnote-ref" id="fnref:94" href="#fn:94">94</a> Low, once-a-decade fires are known to have helped specimens live for half a millennium or more.<a class="footnote-ref" id="fnref:95" href="#fn:95">95</a> The tree has thick bark, and its buds are protected by needles, allowing even some younger individuals to survive weaker fires.<a class="footnote-ref" id="fnref:96" href="#fn:96">96</a> In addition to being adapted to dry, fire-affected areas, the species often appears on the edges of deserts as it is comparatively drought resistant, partly due to the ability to close its leaf pores.<a class="footnote-ref" id="fnref:97" href="#fn:97">97</a> It can also draw some of its water from sandy soils.<a class="footnote-ref" id="fnref:98" href="#fn:98">98</a> Despite being relatively widespread in the American West, it is <a href="/facts/Shade_tolerance/JKkK4J9e">intolerant of shade</a>.<a class="footnote-ref" id="fnref:99" href="#fn:99">99</a>
Pinus ponderosa needles are the only known food of the <a href="/facts/Caterpillar/PMgzj7F7">caterpillars</a> of the <a href="/facts/Gelechiidae/CTrwYjGq">gelechiid</a> <a href="/facts/Moth/bPrkvkGh">moth</a> Chionodes retiniella.<a class="footnote-ref" id="fnref:100" href="#fn:100">100</a> <a href="/facts/Blue_stain_fungus/bLc9Izgw">Blue stain fungus</a>, Grosmannia clavigera, is introduced in sapwood of P. ponderosa from the galleries of all species in the genus <a href="/facts/Dendroctonus/Dcd3Kwqz">Dendroctonus</a> (<a href="/facts/Mountain_pine_beetle/AG9EjhNM">mountain pine beetle</a>), which has caused much damage. <a href="/facts/Dendroctonus_brevicomis/PCCERxIb">Western pine</a> and other beetles can be found consuming the bark.<a class="footnote-ref" id="fnref:101" href="#fn:101">101</a> The seeds are eaten by squirrels, chipmunks, quail, grouse, and <a href="/facts/Clark%2527s_nutcracker/WWNdqwrK">Clark's nutcracker</a>, while mule deer browse the seedlings.<a class="footnote-ref" id="fnref:102" href="#fn:102">102</a> <a href="/facts/American_black_bear/lezPKsnd">American black bears</a> can climb up to 12 feet up a ponderosa.<a class="footnote-ref" id="fnref:103" href="#fn:103">103</a>
Various animals nest in the ponderosa pines, such as the <a href="/facts/Piliated_woodpecker/dyKgNvcN">piliated woodpecker</a>.<a class="footnote-ref" id="fnref:104" href="#fn:104">104</a>

<h3>Pathology</h3>
Pinus ponderosa is affected by <a href="/facts/Armillaria/CSfeMAXt">Armillaria</a>, <a href="/facts/Phaeolus_schweinitzii/mh2JT25f">Phaeolus schweinitzii</a>, <a href="/facts/Fomes/BGjdXEqc">Fomes pini</a>, Atropellis canker, <a href="/facts/Dwarf_mistletoe/CPDTj2BY">dwarf mistletoe</a>, Polyporus anceps, Verticicladiella, Elytroderma <a href="/facts/Cyclaneusma_needle_cast/FkWw8TzR">needle cast</a>, and <a href="/facts/Western_gall_rust/t3gYsUTW">western gall rust</a>.<a class="footnote-ref" id="fnref:105" href="#fn:105">105</a>

<h3>As an invasive species</h3>
Pinus ponderosa is classed as a "<a href="/facts/Wilding_conifer/SLs4ynPA">wilding pine</a>" and spreads as an <a href="/facts/Invasive_species/Ya1v6RGx">invasive species</a> throughout the high country of New Zealand, where it is beginning to take over, causing the native species of plants not to be able to grow in those locations.<a class="footnote-ref" id="fnref:106" href="#fn:106">106</a><a class="footnote-ref" id="fnref:107" href="#fn:107">107</a> It is also considered a "weed" in parts of Australia.<a class="footnote-ref" id="fnref:108" href="#fn:108">108</a>

<h2 id="uses">Uses</h2>
Native Americans consumed the seeds and sweet inner bark. They chewed the dried pitch, which was also used as a salve. They used the limbs and branches as firewood and building material, and the trunks were carved into canoes. The needles and roots were made into baskets. The needles were also boiled into a solution to treat coughs and fevers.<a class="footnote-ref" id="fnref:109" href="#fn:109">109</a>
In the 19th and 20th centuries, old-growth trees were widely used by settlers as lumber, including for railroads. Younger trees are of poor quality for lumber due to the tendency to warp.<a class="footnote-ref" id="fnref:110" href="#fn:110">110</a>

<h3>Cultivation</h3>

Cultivated as a <a href="/facts/Bonsai/g4wLe7ak">bonsai</a>, ponderosas are prized for their rough, flaky bark, contorted trunks, flexible limbs, and dramatic deadwood. Collected specimens can be wildly sculpted by their environment, resulting in beautiful twisted trunks, limbs and deadwood. In the mountains they can be found growing in pockets in the rock, stunting their growth. The main challenge for this species in bonsai cultivation is the natural long length of its needles, which takes years of training and care to reduce.<a class="footnote-ref" id="fnref:111" href="#fn:111">111</a>
This species is grown as an ornamental plant in parks and large gardens.<a class="footnote-ref" id="fnref:112" href="#fn:112">112</a>

<h3>In nuclear testing</h3>
During <a href="/facts/Operation_Upshot%25E2%2580%2593Knothole/RksKPjV9">Operation Upshot–Knothole</a> in 1953, a nuclear test was performed in which 145 ponderosa pines were cut down by the <a href="/facts/United_States_Forest_Service/NRzYYHhc">United States Forest Service</a> and transported to <a href="/facts/Area_5_(NTS)/1hcB39QD">Area 5</a> of the <a href="/facts/Nevada_Test_Site/eWg04MIr">Nevada Test Site</a>, where they were planted into the ground and exposed to a nuclear blast to see what the blast wave would do to a forest. The trees were partially burned and blown over.<a class="footnote-ref" id="fnref:113" href="#fn:113">113</a>

<h2 id="culture">Culture</h2>
Pinus ponderosa is the official state tree of Montana. In a 1908 poll to determine the state tree, Montana schoolchildren chose the tree over the Douglas fir, American larch, and cottonwood. However, the tree was not officially named the state tree until 1949.<a class="footnote-ref" id="fnref:114" href="#fn:114">114</a>

<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/Southern_yellow_pine/02NSNNPQ">Southern yellow pine</a></li></ul>

<h2 id="general-references">General references</h2>

<ul><li><a href="/facts/J._Smeaton_Chase/jQECwE3u">Chase, J. Smeaton</a> (1911). <a href="https://archive.org/details/conebearingtrees00chas/page/16/mode/2up">Cone-bearing Trees of the California Mountains</a>. <a href="/facts/Carl_Eytel/mKonys58">Eytel, Carl</a> (illustrations). Chicago: <a href="/facts/A.C._McClurg_%2526_Co./usN4zclK">A.C. McClurg & Co.</a> pp. 16–18. <a href="/facts/LCCN_(identifier)/5hb5Cw2V">LCCN</a> <a href="https://lccn.loc.gov/11004975">11004975</a>. <a href="/facts/OCLC_(identifier)/Yqad8waq">OCLC</a> <a href="https://search.worldcat.org/oclc/3477527">3477527</a>.</li>
<li>Farjon, A. (2013). <a href="https://www.iucnredlist.org/species/42401/2977432">"Pinus ponderosa"</a>. <a href="/facts/IUCN_Red_List/8gemqCLu">IUCN Red List of Threatened Species</a>. 2013: e.T42401A2977432. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.2305%2FIUCN.UK.2013-1.RLTS.T42401A2977432.en">10.2305/IUCN.UK.2013-1.RLTS.T42401A2977432.en</a>. Retrieved 12 November 2021.</li>
<li>Conkle, MT; Critchfield, WB (1988). "Genetic variation and hybridization of ponderosa pine". In Baumgartner, DM; Lotan, JE (eds.). Ponderosa pine the species and its management. Cooperative Extension, Washington State University. pp. 27–44.</li>
<li>Critchfield, WB (1984). "Crossability and relationships of Washoe Pine". Madroño. 31: 144–170.</li>
<li>Critchfield, WB; Allenbaugh, GL (1965). "Washoe pine on the Bald Mountain Range, California". Madroño. 18: 63–64.</li>
<li>Farjon, A (2005). Pines (2nd ed.). Leiden & Boston: Brill. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 90-04-13916-8.</li>
<li>Haller, JR (1962). Variation and hybridization in ponderosa and Jeffrey pines. University of California Publications in Botany. Vol. 34. pp. 123–166.</li>
<li>Haller, JR (1965). "The role of 2-needle fascicles in the adaptation and evolution of ponderosa pine". Brittonia. 17 (4): 354–382. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1965Britt..17..354H">1965Britt..17..354H</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.2307%2F2805029">10.2307/2805029</a>. <a href="/facts/JSTOR_(identifier)/YTeVmaJ7">JSTOR</a> <a href="https://www.jstor.org/stable/2805029">2805029</a>. <a href="/facts/S2CID_(identifier)/ldJsHa2Y">S2CID</a> <a href="https://api.semanticscholar.org/CorpusID:32656015">32656015</a>.</li>
<li>Haller, JR; Vivrette, NJ (2011). <a href="https://doi.org/10.5642%2Faliso.20112901.07">"Ponderosa pine revisited"</a>. Aliso. 29 (1): 53–57. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.5642%2Faliso.20112901.07">10.5642/aliso.20112901.07</a>.</li>
<li>Lauria, F (1991). "Taxonomy, systematics, and phylogeny of Pinus subsection Ponderosae Loudon (Pinaceae). Alternative concepts". Linzer Biol. Beitr. 23 (1): 129–202.</li>
<li>Lauria, F (1996). "The identity of Pinus ponderosa Douglas ex C.Lawson (Pinaceae)". Linzer Biol. Beitr. 28 (2): 999–1052.</li>
<li>Lauria, F (1996). "Typification of Pinus benthamiana Hartw. (Pinaceae), a taxon deserving renewed botanical examination". Ann. Naturhist. Mus. Wien. 98 (B Suppl): 427–446.</li>
<li>Mirov, NT (1929). "Chemical analysis of the oleoresins as a means of distinguishing Jeffrey pine and western yellow pine". Journal of Forestry. 27: 176–187.</li>
<li>Van Haverbeke, DF (1986). Genetic variation in ponderosa pine: A 15-Year Test of provenances in the Great Plains. USDA Forest Service. Research Paper RM-265.</li>
<li>Wagener, WW (1960). "A comment on cold susceptibility of ponderosa and Jeffrey pines". Madroño. 15: 217–219.</li></ul>

<h2 id="external-links">External links</h2>

<a href="/facts/Wikimedia_Commons/lzkBFxTg">Wikimedia Commons</a> has media related to:
Pinus ponderosa (category)

<ul><li><a href="https://plants.usda.gov/core/profile?symbol=PIPO">USDA Plants Profile for Pinus ponderosa (ponderosa pine)</a></li>
<li><a href="http://www.conifers.org/pi/pin/ponderosa.htm">Gymnosperm Database: Pinus ponderosa</a></li>
<li><a href="http://www.calflora.org/cgi-bin/species_query.cgi?where-calrecnum=6521">Calflora Database: Pinus ponderosa (ponderosa pine, western yellow pine)</a></li>
<li><a href="https://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=38293">Jepson Manual eFlora (TJM2) treatment of Pinus ponderosa</a></li>
<li><a href="http://calphotos.berkeley.edu/cgi/img_query?where-taxon=Pinus+ponderosa">Pinus ponderosa</a> in the <a href="/facts/CalPhotos/eCY49YYF">CalPhotos</a> photo database, <a href="/facts/University_of_California%2c_Berkeley/MXVEjklr">University of California, Berkeley</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1">NRCS. "Pinus ponderosa". PLANTS Database. United States Department of Agriculture (USDA). Retrieved 31 January 2016; with distribution map.{{cite web}}: CS1 maint: postscript (link) <a href="/wiki/Natural_Resources_Conservation_Service" target="_blank">/wiki/Natural_Resources_Conservation_Service</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></li>
<li id="fn:2">Moore, Gerry; Kershner, Bruce; Tufts, Craig; Mathews, Daniel; Nelson, Gil; Spellenberg, Richard; Thieret, John W.; Purinton, Terry; Block, Andrew (2008). National Wildlife Federation Field Guide to Trees of North America. New York, New York: Sterling. p. 89. ISBN 978-1-4027-3875-3. <a href="978-1-4027-3875-3" target="_blank">978-1-4027-3875-3</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></li>
<li id="fn:3">BSBI List 2007 (xls). Botanical Society of Britain and Ireland. Archived from the original (xls) on 2015-06-26. Retrieved 2014-10-17. <a href="https://web.archive.org/web/20150626140254/http://www.bsbi.org.uk/BSBIList2007.xls" target="_blank">https://web.archive.org/web/20150626140254/http://www.bsbi.org.uk/BSBIList2007.xls</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></li>
<li id="fn:4">Marcus, M, P (1969). United States Pines, Local Nomenclatures and Their Origins. Bonanza Books. pp. 420–422.{{cite book}}: CS1 maint: multiple names: authors list (link) <a href="/wiki/Template:Cite_book" target="_blank">/wiki/Template:Cite_book</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></li>
<li id="fn:5">Safford, H.D. 2013. Natural Range of Variation (NRV) for yellow pine and mixed conifer forests in the bioregional assessment area, including the Sierra Nevada, southern Cascades, and Modoc and Inyo National Forests. Unpublished report. USDA Forest Service, Pacific Southwest Region, Vallejo, CA, [1] <a href="https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5434331.pdf" target="_blank">https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5434331.pdf</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></li>
<li id="fn:6">"Ponderosa pine named Spokane's official city tree | The Spokesman-Review". www.spokesman.com. Retrieved 2021-02-04. <a href="https://www.spokesman.com/stories/2014/apr/22/ponderosa-pine-named-spokane-official-city-tree/" target="_blank">https://www.spokesman.com/stories/2014/apr/22/ponderosa-pine-named-spokane-official-city-tree/</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></li>
<li id="fn:7">Groover, Heidi. "Hey, Spokane, you now have a city tree". Inlander. Retrieved 2021-02-04. <a href="https://www.inlander.com/Bloglander/archives/2014/04/22/hey-spokane-you-now-have-a-city-tree" target="_blank">https://www.inlander.com/Bloglander/archives/2014/04/22/hey-spokane-you-now-have-a-city-tree</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></li>
<li id="fn:8">Lauria, F. (1996). "The identity of Pinus ponderosa Douglas ex C. Lawson (Pinaceae)" (PDF). Linzer Biologische Beitraege. <a href="https://www.zobodat.at/pdf/LBB_0028_2_0999-1052.pdf" target="_blank">https://www.zobodat.at/pdf/LBB_0028_2_0999-1052.pdf</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></li>
<li id="fn:9">The agriculturist's manual: being a familiar description of agricultural plants cultivated in Europe. Edinburgh U.K.: William Blackwood and Sons. 1836. <a href="#fnref:9" class="footnote-back-ref">↩</a></li>
<li id="fn:10">Dickson, Tom. "Ponderosa Pine". Montana Outdoors. Montana Fish, Wildlife & Parks. Archived from the original on April 29, 2015. Retrieved February 18, 2015. <a href="https://web.archive.org/web/20150429025518/http://fwp.mt.gov/mtoutdoors/HTML/articles/portraits/ponderosapine.htm" target="_blank">https://web.archive.org/web/20150429025518/http://fwp.mt.gov/mtoutdoors/HTML/articles/portraits/ponderosapine.htm</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></li>
<li id="fn:11">"American Profile". March 13, 2021. <a href="https://americanprofile.com/articles/ponderosa-pine-montana-state-tree/" target="_blank">https://americanprofile.com/articles/ponderosa-pine-montana-state-tree/</a> <a href="#fnref:11" class="footnote-back-ref">↩</a></li>
<li id="fn:12">Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. pp. 49–57. ISBN 978-1-68051-329-5. OCLC 1141235469. <a href="978-1-68051-329-5" target="_blank">978-1-68051-329-5</a> <a href="#fnref:12" class="footnote-back-ref">↩</a></li>
<li id="fn:13">Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. pp. 49–57. ISBN 978-1-68051-329-5. OCLC 1141235469. <a href="978-1-68051-329-5" target="_blank">978-1-68051-329-5</a> <a href="#fnref:13" class="footnote-back-ref">↩</a></li>
<li id="fn:14">Callaham, Robert Z. (September 2013). "Pinus ponderosa: A Taxonomic Review with Five Subspecies in the United States" (PDF). USDA Forest Service. PSW RP-264. <a href="http://www.fs.fed.us/psw/publications/documents/psw_rp264/psw_rp264.pdf" target="_blank">http://www.fs.fed.us/psw/publications/documents/psw_rp264/psw_rp264.pdf</a> <a href="#fnref:14" class="footnote-back-ref">↩</a></li>
<li id="fn:15">Callaham, Robert Z. (September 2013). "Pinus ponderosa: Geographic Races and Subspecies Based on Morphological Variation" (PDF). USDA Forest Service. PSW RP-265. <a href="http://www.fs.fed.us/psw/publications/documents/psw_rp265/psw_rp265.pdf" target="_blank">http://www.fs.fed.us/psw/publications/documents/psw_rp265/psw_rp265.pdf</a> <a href="#fnref:15" class="footnote-back-ref">↩</a></li>
<li id="fn:16">Eckenwalder, James (2009). Conifers of the World. Portland, Oregon: Timber Press. ISBN 978-0-88192-974-4. <a href="978-0-88192-974-4" target="_blank">978-0-88192-974-4</a> <a href="#fnref:16" class="footnote-back-ref">↩</a></li>
<li id="fn:17">Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. pp. 49–57. ISBN 978-1-68051-329-5. OCLC 1141235469. <a href="978-1-68051-329-5" target="_blank">978-1-68051-329-5</a> <a href="#fnref:17" class="footnote-back-ref">↩</a></li>
<li id="fn:18">Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. pp. 49–57. ISBN 978-1-68051-329-5. OCLC 1141235469. <a href="978-1-68051-329-5" target="_blank">978-1-68051-329-5</a> <a href="#fnref:18" class="footnote-back-ref">↩</a></li>
<li id="fn:19">Smith, Richard H. (1977). Monoterpenes of ponderosa pine in Western United States. USDA Forest Service. Tech. Bull. 1532. <a href="#fnref:19" class="footnote-back-ref">↩</a></li>
<li id="fn:20">Schoenherr, Allan A. (1995). A Natural History of California. University of California Press. p. 111. <a href="#fnref:20" class="footnote-back-ref">↩</a></li>
<li id="fn:21">Kricher, John C (1998). A field guide to Rocky Mountain and southwest forests. Houghton Mifflin. p. 194. <a href="#fnref:21" class="footnote-back-ref">↩</a></li>
<li id="fn:22">Schoenherr, Allan A. (1995). A Natural History of California. University of California Press. p. 111. <a href="#fnref:22" class="footnote-back-ref">↩</a></li>
<li id="fn:23">Kricher, John C. (1998). A field guide to California and Pacific Northwest forests. Houghton Mifflin. p. 107. <a href="#fnref:23" class="footnote-back-ref">↩</a></li>
<li id="fn:24">Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. pp. 49–57. ISBN 978-1-68051-329-5. OCLC 1141235469. <a href="978-1-68051-329-5" target="_blank">978-1-68051-329-5</a> <a href="#fnref:24" class="footnote-back-ref">↩</a></li>
<li id="fn:25">"Pacific ponderosa pine". National Register of Big Trees. American Forests. <a href="http://www.americanforests.org/resources/bigtrees/register.php?details=3961" target="_blank">http://www.americanforests.org/resources/bigtrees/register.php?details=3961</a> <a href="#fnref:25" class="footnote-back-ref">↩</a></li>
<li id="fn:26">Earle, Christopher J., ed. (2018). "Pinus ponderosa subsp. benthamiana". The Gymnosperm Database. Retrieved January 9, 2018. <a href="http://www.conifers.org/pi/Pinus_ponderosa_benthamiana.php" target="_blank">http://www.conifers.org/pi/Pinus_ponderosa_benthamiana.php</a> <a href="#fnref:26" class="footnote-back-ref">↩</a></li>
<li id="fn:27">Fattig, Paul (January 23, 2011). "Tallest of the tall". Mail Tribune. Medford, Oregon. Archived from the original on September 23, 2012. Retrieved January 27, 2011. <a href="https://web.archive.org/web/20120923095326/http://www.mailtribune.com/apps/pbcs.dll/article?AID=%2F20110123%2FNEWS%2F101230353%2F" target="_blank">https://web.archive.org/web/20120923095326/http://www.mailtribune.com/apps/pbcs.dll/article?AID=%2F20110123%2FNEWS%2F101230353%2F</a> <a href="#fnref:27" class="footnote-back-ref">↩</a></li>
<li id="fn:28">"Pinus lambertiana". Gymnosperm Database. Retrieved 2021-04-24. <a href="https://www.conifers.org/pi/Pinus_lambertiana.php" target="_blank">https://www.conifers.org/pi/Pinus_lambertiana.php</a> <a href="#fnref:28" class="footnote-back-ref">↩</a></li>
<li id="fn:29">Riggs, Keith. "Oregon Forest Home for World's Tallest Living Pine Tree". US Forest Service. Retrieved 2021-04-24. <a href="https://www.usda.gov/media/blog/2011/12/08/oregon-forest-home-worlds-tallest-living-pine-tree" target="_blank">https://www.usda.gov/media/blog/2011/12/08/oregon-forest-home-worlds-tallest-living-pine-tree</a> <a href="#fnref:29" class="footnote-back-ref">↩</a></li>
<li id="fn:30">"Pinus ponderosa Douglas ex C.Lawson". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 21 March 2025. <a href="https://powo.science.kew.org/taxon/307165-2" target="_blank">https://powo.science.kew.org/taxon/307165-2</a> <a href="#fnref:30" class="footnote-back-ref">↩</a></li>
<li id="fn:31">Lawson, Charles; Lawson, Peter (1836). The Agriculturist's Manual : Being a Familiar Description of the Agricultural Plants Cultivated in Europe : Including Practical Observations Respecting Those Suited to the Climate of Great Britain and Forming a Report of Lawson's Agricultural Museum in Edinburgh. Edinburgh, Scotland: William Blackwood and Sons, Edinburgh: Thomas Cadell, 141 Strand, London; and W. Curry Jun. & Co., Dublin. pp. 354–355. Retrieved 22 March 2025. <a href="/wiki/Charles_Lawson_(nurseryman)" target="_blank">/wiki/Charles_Lawson_(nurseryman)</a> <a href="#fnref:31" class="footnote-back-ref">↩</a></li>
<li id="fn:32">Callaham, Robert Z. (September 2013). "Pinus ponderosa: A Taxonomic Review with Five Subspecies in the United States" (PDF). USDA Forest Service. PSW RP-264. <a href="http://www.fs.fed.us/psw/publications/documents/psw_rp264/psw_rp264.pdf" target="_blank">http://www.fs.fed.us/psw/publications/documents/psw_rp264/psw_rp264.pdf</a> <a href="#fnref:32" class="footnote-back-ref">↩</a></li>
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<li id="fn:97">Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. pp. 49–57. ISBN 978-1-68051-329-5. OCLC 1141235469. <a href="978-1-68051-329-5" target="_blank">978-1-68051-329-5</a> <a href="#fnref:97" class="footnote-back-ref">↩</a></li>
<li id="fn:98">Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. pp. 49–57. ISBN 978-1-68051-329-5. OCLC 1141235469. <a href="978-1-68051-329-5" target="_blank">978-1-68051-329-5</a> <a href="#fnref:98" class="footnote-back-ref">↩</a></li>
<li id="fn:99">Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. pp. 49–57. ISBN 978-1-68051-329-5. OCLC 1141235469. <a href="978-1-68051-329-5" target="_blank">978-1-68051-329-5</a> <a href="#fnref:99" class="footnote-back-ref">↩</a></li>
<li id="fn:100">Furniss, RL; Carolin, VM (1977). Western Forest Insects. US Department of Agriculture Forest Service. p. 177. Miscellaneous Publication 1339. <a href="#fnref:100" class="footnote-back-ref">↩</a></li>
<li id="fn:101">Patterson, Patricia A. (1985). Field Guide to the Forest Plants of Northern Idaho (PDF). United States Department of Agriculture Forest Service. p. 20. <a href="https://www.fs.fed.us/rm/pubs_int/int_gtr180.pdf" target="_blank">https://www.fs.fed.us/rm/pubs_int/int_gtr180.pdf</a> <a href="#fnref:101" class="footnote-back-ref">↩</a></li>
<li id="fn:102">Peattie, Donald Culross (1953). A Natural History of Western Trees. New York: Bonanza Books. pp. 83–84, 86. <a href="/wiki/Donald_C._Peattie" target="_blank">/wiki/Donald_C._Peattie</a> <a href="#fnref:102" class="footnote-back-ref">↩</a></li>
<li id="fn:103">Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. pp. 49–57. ISBN 978-1-68051-329-5. OCLC 1141235469. <a href="978-1-68051-329-5" target="_blank">978-1-68051-329-5</a> <a href="#fnref:103" class="footnote-back-ref">↩</a></li>
<li id="fn:104">Bull, Evelyn L. (1987). "Ecology of the pileated woodpecker in northeastern Oregon". The Journal of Wildlife Management. 51 (2): 472–481. doi:10.2307/3801036. JSTOR 3801036. On the Stakey Experimental Forest in northeastern Oregon, piliated woodpeckers nested in dead ponderosa pine <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:104" class="footnote-back-ref">↩</a></li>
<li id="fn:105">Patterson, Patricia A. (1985). Field Guide to the Forest Plants of Northern Idaho (PDF). United States Department of Agriculture Forest Service. p. 20. <a href="https://www.fs.fed.us/rm/pubs_int/int_gtr180.pdf" target="_blank">https://www.fs.fed.us/rm/pubs_int/int_gtr180.pdf</a> <a href="#fnref:105" class="footnote-back-ref">↩</a></li>
<li id="fn:106">"GISD". www.iucngisd.org. Retrieved 2021-03-10. <a href="http://www.iucngisd.org/gisd/species.php?sc=890" target="_blank">http://www.iucngisd.org/gisd/species.php?sc=890</a> <a href="#fnref:106" class="footnote-back-ref">↩</a></li>
<li id="fn:107">Wilding Pines, Quick ID (October 2018). "Wilding Conifer:Quick ID Guide" (PDF). wildingconifers.org.nz. Retrieved March 10, 2021. <a href="https://www.wildingconifers.org.nz/assets/Uploads/Wilding-Conifer-QUICK-ID-GUIDE6.pdf" target="_blank">https://www.wildingconifers.org.nz/assets/Uploads/Wilding-Conifer-QUICK-ID-GUIDE6.pdf</a> <a href="#fnref:107" class="footnote-back-ref">↩</a></li>
<li id="fn:108">Victorian Resources Online, Agriculture Victoria. "Ponderosa pine (Pinus ponderosa)". vro.agriculture.vic.gov.au. Retrieved 2022-03-11. <a href="http://vro.agriculture.vic.gov.au/dpi/vro/vrosite.nsf/pages/weeds_ponderosa-pine" target="_blank">http://vro.agriculture.vic.gov.au/dpi/vro/vrosite.nsf/pages/weeds_ponderosa-pine</a> <a href="#fnref:108" class="footnote-back-ref">↩</a></li>
<li id="fn:109">Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. pp. 49–57. ISBN 978-1-68051-329-5. OCLC 1141235469. <a href="978-1-68051-329-5" target="_blank">978-1-68051-329-5</a> <a href="#fnref:109" class="footnote-back-ref">↩</a></li>
<li id="fn:110">Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. pp. 49–57. ISBN 978-1-68051-329-5. OCLC 1141235469. <a href="978-1-68051-329-5" target="_blank">978-1-68051-329-5</a> <a href="#fnref:110" class="footnote-back-ref">↩</a></li>
<li id="fn:111">"Ponderosa Pines (Pinus ponderosa) as a Bonsai – East Bay Bonsai Society". <a href="https://www.eastbaybonsai.org/ebbs-spotlight/ponderosa-pines-pinus-ponderosa-as-a-bonsai/" target="_blank">https://www.eastbaybonsai.org/ebbs-spotlight/ponderosa-pines-pinus-ponderosa-as-a-bonsai/</a> <a href="#fnref:111" class="footnote-back-ref">↩</a></li>
<li id="fn:112">"Ponderosa Pine - Pacific and Columbia sub species - Potted tree seedling - Landscape, Timber Tree, Bonsai". Archived from the original on September 25, 2021. <a href="https://web.archive.org/web/20210925004228/https://scenichillfarmnursery.com/products/ponderosa-pine-12-20-inch-potted-tree-seedling-landscape-timber-tree-bonsai#:~:text=Grown%20an%20ornamental%20plant%20in,makes%20an%20excellent%20bonsai%20tree" target="_blank">https://web.archive.org/web/20210925004228/https://scenichillfarmnursery.com/products/ponderosa-pine-12-20-inch-potted-tree-seedling-landscape-timber-tree-bonsai#:~:text=Grown%20an%20ornamental%20plant%20in,makes%20an%20excellent%20bonsai%20tree</a> <a href="#fnref:112" class="footnote-back-ref">↩</a></li>
<li id="fn:113">Finkbeiner, Ann (May 31, 2013). "How Do We Know Nuclear Bombs Blow Down Forests?". Slate.com. Retrieved May 31, 2013. <a href="http://www.slate.com/articles/health_and_science/science/2013/05/nuclear_weapons_tests_on_trees_jasons_moved_a_forest_to_the_nevada_test.html" target="_blank">http://www.slate.com/articles/health_and_science/science/2013/05/nuclear_weapons_tests_on_trees_jasons_moved_a_forest_to_the_nevada_test.html</a> <a href="#fnref:113" class="footnote-back-ref">↩</a></li>
<li id="fn:114">"Ponderosa Pine: Montana State Tree". State Symbols USA. 14 October 2014. Retrieved 13 February 2020. <a href="https://statesymbolsusa.org/symbol-official-item/montana/state-tree/ponderosa-pine" target="_blank">https://statesymbolsusa.org/symbol-official-item/montana/state-tree/ponderosa-pine</a> <a href="#fnref:114" class="footnote-back-ref">↩</a></li>
</ol>

Pinus ponderosa open-in-new

Pinus ponderosa