{{Short description|Species of flowering plant}} {{Speciesbox | image = Castilleja integra - Michael Tidwell 01.jpg | image_caption = Coconino National Forest, Arizona, US | status = {{TNCStatus}} | status_system = TNC | status_ref = <ref name="NatureServe" /> | genus = Castilleja | species = integra | authority = A.Gray | range_map = Castilleja integra range map.png | range_map_caption = The range of ''Castilleja integra'' in western North America | synonyms_ref = <ref name="POWO" /> | synonyms = {{Species list | Castilleja angustifolia | A.Gray | Castilleja elongata | Pennell | Castilleja gloriosa | Britton }} }}
'''''Castilleja integra''''', with the common names '''orange paintbrush''', '''Southwestern paintbrush''', and '''wholeleaf paintbrush''', is a partially parasitic herbaceous perennial plant native to the Southwestern United States and Northern Mexico. The species produces a relatively large amount of nectar and is attractive to hummingbirds. It is better suited to cultivation than most other species in the paintbrush genus (''Castilleja'') and is therefore used in xeriscape gardens and naturalistic meadows, even outside its native range.
==Description== Mature individuals of ''Castilleja integra'' are typically {{Convert|9-50|cm|sp=us|sigfig=2}} in size, though they have been reported to grow as tall as {{Convert|100|cm|sp=us}}.<ref name="FNA" /><ref name="Flora 4corners" /> All above ground parts of the plants, the leaves, bracts, stems, and flowers, are covered in light coating of soft down, called tomentum by botanists.<ref name="Jewels">{{cite book |last1=Barr |first1=Claude A. |title=Jewels of the plains : wild flowers of the Great Plains grasslands and hills |date=1983 |publisher=University of Minnesota Press |location=Minneapolis |isbn=0-8166-1127-0 |pages=54–55}}</ref><ref name="FNA" /> The herbaceous stems regrow each season from a hard, woody structure called a caudex that is atop a substantial taproot or stout branched roots.<ref name="FNA">{{cite web |last1=Egger |first1=J. Mark |last2=Zika |first2=Peter F. |last3=Wilson |first3=Barbara L. |last4=Brainerd |first4=Richard E. |last5=Otting |first5=Nick |title=''Castilleja integra'' - FNA |url=http://floranorthamerica.org/Castilleja_integra |website=Flora of North America |access-date=12 May 2023 |archive-date=12 May 2023 |archive-url=https://web.archive.org/web/20230512205823/http://floranorthamerica.org/Castilleja_integra |url-status=live }}</ref> The stems either grow straight up from the ground (erect stems) or have a curved bend at their base to grow outwards a short distance then upwards (ascending stems). ''C. integra'' may have just one solitary stem or several, they are always unbranched near the base, but may have short branches near the end of the stems.<ref name="FNA" /><ref name="Flora 4corners" />
[[File:Castilleja integra - Patrick Alexander 01.jpg|thumb|left|''Castilleja integra'' with purple leaves near Carson National Forest, Rio Arriba County, New Mexico]] ''Castilleja integra'' has leaves that may range in color from purplish to fully green, but will usually be pale or dusty looking because of the fine, unbranched hairs on the surface. The leaves are always narrow, but vary from being very narrow and thin like a blade of grass (linear leaves) to being almost rectangular, but still not very wide (narrowly oblong leaves).<ref name="FNA" /> The leaves are usually whole without divisions or toothed edges (entire),<ref name="Jewels" /> but will occasionally have two shallow divisions near the end of the leaf, giving it three lobes.<ref name="FNA" /> The edges of the leaves can be wavy, but are never thick or fleshy. Often the edges roll inward towards the center of the leaf (involute).<ref name="Flora 4corners" /><ref name="Flora of CO" /> The end of the leaves have a narrow point or slightly rounded tip. The length of the leaves can be {{Convert|1-9|cm|sp=us|sigfig=2}}, but usually between {{Convert|2-7|cm|sp=us|sigfig=2}}.<ref name="FNA" />
[[File:Castilleja integra - Rod 01.jpg|thumb|left|''Castilleja integra'' flower, lighter color form, Lost Creek Wilderness, Park County, Colorado]] The cluster of flowers and the surrounding bracts (the inflorescence) can be 2 to 15 centimeters long,<ref name="FNA" /> though usually less than 10 centimeters.<ref name="Flora 4corners" /> The width is {{Convert|1.5-4|cm|sp=us|sigfig=2}}.<ref name="FNA" /> The showy bracts are variable in color with occasional instances of rose, crimson, cerise, pale salmon, or pale yellow individuals, but most often an intense red-orange or orange flame color.<ref name="Jewels" /><ref name="FNA" /> Very often they are the same color on the whole of the bract, but sometimes they are green or a pale straw color at the base. The bracts may be shaped like a skinny spear point (lanceolate), oblong like the leaves, egg shaped (obovate), or intermediate between any of these shapes. The ends of the bracts can be undivided or have three or (rarely) five lobes. The middle or lone end of the bract is always blunt while when side lobes are present their ends are narrow (acute).<ref name="FNA" /> The total length of the bracts is 20 to 40 millimeters.<ref name="Flora 4corners" />
The sepals (calyx) have the same color and texture as the bracts and may be 18–38 millimeters long, but are more often between 21 and 35 millimeters in length. The sepals are united into a tube for most of their length with splits towards the end. The splits on the top and bottom are 25–35% of the length, as much as 6–18 millimeters long, but more often 9–16 millimeters in length. The splits towards the sides are shorter, 10–15% of the tube's length. The lobes formed by the splits are lanceolate or triangular in shape with a rounded or narrow point.<ref name="FNA" />
''Castilleja integra'' has true petals that are fused into a tube for much of their length. The overall length of the petals is usually 25–45 millimeters, but may be as little as 21 mm or as much as 50 mm in exceptional cases. The length of the tube portion of the flower petals is 17–33 millimeters. The beak, the pointed end of the flower petals, is green in color on the upper surface and either only slightly shorter than the sepals to projecting well beyond them. The beak ranges in size from 8–18 millimeters, but is most often in the range of 10–17 millimeters. The lower lip is always dark green and 20% as long as the beak.<ref name="FNA" />
thumb|left|''Castilleja integra'' seeds The flowering season is very extended due to the wide range of elevations where the flowers are found, most often in March to October, but occasionally as early as January.<ref name="FNA" /> In Colorado the blooming season starts in June and continues through August.<ref name="Natives 8thEd." /> The seeds are contained within a capsule 12–16 millimeters long.<ref name="Flora of CO" />
Similar species that it may be confused with include ''Castilleja lanata'' and ''Castilleja miniata''. The combination of undivided leaves that strongly roll inward (involute), the soft unbranched downy hairs, and usually undivided bracts help to distinguish ''Castilleja integra'' from its relatives.<ref name="FNA" />
===Chemistry=== ''Castilleja integra'' plants contain iridoids bound as glycosides at different concentrations in different parts of the plant. Macfadienoside is found in all parts of the plants, but at especially high levels in the leaves. Similarly, methyl shanziside is much more common in leaves and found at very low levels in bracts or flowers. On the other hand, catalpol is mainly or only found in the flowers. These differences influence what parts of the plants are consumed by herbivores.<ref>{{cite journal |last1=Haan |first1=Nathan L. |last2=Bowers |first2=M. Deane |last3=Bakker |first3=Jonathan D. |title=Preference, performance, and chemical defense in an endangered butterfly using novel and ancestral host plants |journal=Scientific Reports |date=14 January 2021 |volume=11 |issue=1 |page=992 |doi=10.1038/s41598-020-80413-y|pmid=33446768 |bibcode=2021NatSR..11..992H |doi-access=free |pmc=7809109 }}</ref>
''Castilleja integra'' will also transfer certain alkaloids from host plants to its own tissues. For example senecionine, a pyrrolizidine alkaloid, is transferred from ''Liatris punctata'' (dotted gayfeathers) and ''Senecio'' species to itself. Similarly lupanine, one of the quinolizidine alkaloids, is transferred from ''Lupinus'' (lupins).<ref>{{cite book |last1=Wink |first1=Michael |title=Modern Alkaloids |date=24 October 2007 |publisher=Wiley |isbn=978-3-527-31521-5 |page=22 |edition=1 |language=en |chapter=Ecological Roles of Alkaloids}}</ref> The transfer of senecionine to itself appears to have some benefit in reducing the growth rate of herbivores such as leanira checkerspot caterpillars (''Chlosyne leanira'').<ref name="Alkaloids" /> In other cases, like that of ''Oxytropis sericea'', ''C. integra'' will parasitize the host plant, but does not transfer the alkaloid swainsonine to itself.<ref name="Alkaloids">{{cite book |editor1-last=Roberts |editor1-first=Margaret F. |editor2-last=Wink |editor2-first=Michael |title=Alkaloids : Biochemistry, Ecology, and Medicinal Applications |date=1998 |publisher=Plenum Press |location=New York |isbn=978-0-306-45465-3 |pages=330, 334 |url=https://archive.org/details/alkaloidsbiochem0000unse/page/330 |access-date=24 November 2023}}</ref>
[[File:Castilleja integra - Elliott Gordon 01.jpg|thumb|right|''Castilleja integra'' seed capsules, Sandia Mountain Wilderness, New Mexico]] ==Taxonomy== ''Castilleja integra'' was first scientifically observed in the Organ Mountains of Southern New Mexico near El Paso, Texas, by Charles Wright.<ref>{{cite journal |last1=Pennell |first1=Francis W. |author1-link=Francis W. Pennell |title=The Scrophulariaceae of Eastern Temperate North America |journal=Monographs |date=1935 |volume=1 |page=533 |url=https://archive.org/details/academyofnatural0000fran/page/533 |publisher=The Academy of Natural Sciences of Philadelphia}}</ref> Its first published description was in 1858 by Asa Gray.<ref name="POWO" /><ref>'Rep. U.S. Mex. Bound'. 2(1): 119; by Asa Gray.</ref> Two different chromosome numbers have been observed in ''Castilleja integra'', 2n = 24 and 48.<ref name="FNA" />
Though its naming and classification have never been challenged, a number species or subspecies have previously been described that are now either regarded as illegitimate (''nomen illegitimum'') or as synonyms of ''Castilleja integra''. These include ''Castilleja angustifolia'' described by Asa Gray in 1859, the mistaken ''Castilleja elongata'' described by Francis W. Pennell in 1941, and ''Castilleja gloriosa'' described by James Britten in 1889. Theodore Dru Alison Cockerell recognized that the description of ''Castilleja gloriosa'' was incorrect, but thought it may be a subspecies and described it as ''Castilleja integra'' var. ''gloriosa'' in 1900 along with another subspecies ''Castilleja integra'' var. ''intermedia''. He had previously described another subspecies as ''Castilleja integra'' var. ''gracilis'' in 1890.
As of 2023 Plants of the World Online (POWO), World Flora Online (WFO), and Flora of North America list ''Castilleja integra'' as the correct classification and ''Castilleja gloriosa'' as a synonym.<ref name="POWO" /><ref name="WFO">{{cite web |last1=WFO |title=''Castilleja integra'' A.Gray |url=https://www.worldfloraonline.org/taxon/wfo-0000590266 |website=World Flora Online |access-date=11 November 2023 |date=2023 |archive-date=11 November 2023 |archive-url=https://web.archive.org/web/20231111225121/https://www.worldfloraonline.org/taxon/wfo-0000590266 |url-status=live }}</ref><ref name="FNA" /> It has six heterotypic synonyms in total.<ref name="POWO" />
{|class="wikitable sortable mw-collapsible" id="Synonyms" |+ class="nowrap" | Table of Synonyms ! Name ! Year ! Rank ! Notes |- | ''Castilleja angustifolia'' {{small|A.Gray}} | 1859 |data-sort-value=A | species | nom. illeg. |- | ''Castilleja elongata'' {{small|Pennell}} | 1941 |data-sort-value=A | species | |- | ''Castilleja gloriosa'' {{small|Britton}} | 1889 |data-sort-value=A | species | |- | ''Castilleja integra'' var. ''gloriosa'' {{small|(Britton) Cockerell}} | 1900 |data-sort-value=D | variety | |- | ''Castilleja integra'' var. ''gracilis'' {{small|Cockerell}} | 1890 |data-sort-value=D | variety | |- | ''Castilleja integra'' var. ''intermedia'' {{small|Cockerell}} | 1900 |data-sort-value=D | variety | |}
===Subspecies=== The status of the subspecies of ''Castilleja integra'' is questionable. In 2023 only ''Castilleja integra'' var. ''gloriosa'' and the autonym ''Castilleja integra'' var. ''integra'' are still regarded as a legitimate by some botanists. The USDA Natural Resources Conservation Service PLANTS database (PLANTS)<ref name="USDA" /> and NatureServe<ref name="NatureServe" /> continue to list var. ''gloriosa'' as a legitimate subspecies, while POWO, WFO, and the Flora of North America regard it as part of the normal variation of the species.<ref name="POWO" /><ref name="WFO" /><ref name="FNA" />
===Names=== The species name, ''integra'', refers to the leaves being undivided or entire in botanical terminology.<ref name="Jewels" /> The species has a variety of common names including ''orange paintbrush'',<ref name="Natives 8thEd.">{{cite book |last1=Pesman |first1=M. Walter |title=Meet the Natives |date=1988 |publisher=Denver Botanic Gardens / Pruett Publishing |location=Boulder, Colorado |isbn=978-0-87108-731-7 |page=130 |edition=8th |url=https://archive.org/details/meetnatives0000unse/page/130 |access-date=3 November 2023}}</ref> ''Southwestern paintbrush'',<ref>{{cite book |last1=Mohlenbrock |first1=Robert H. |title=Wildflowers : a Quick Identification Guide to the Wildflowers of North America |date=1987 |publisher=Macmillan Publishing Company |location=New York |isbn=978-0-02-063420-1 |page=120 |url=https://archive.org/details/macmillanfieldgu00mohl/page/120 |access-date=3 November 2023}}</ref> ''scarlet paintbrush'',<ref>{{cite book |last1=Holloway |first1=Joel Ellis |title=A Dictionary of Common Wildflowers of Texas & the Southern Great Plains |date=2005 |publisher=TCU Press |location=Fort Worth, Texas |isbn=978-0-87565-309-9 |page=32 |edition=1st |url=https://archive.org/details/dictionaryofcomm0000holl/page/32 |access-date=3 November 2023}}</ref> ''grassland paintbrush'',<ref>{{cite book |last1=Martin |first1=Laura C. |title=The Wildflower Meadow Book : a Gardener's Guide |date=1986 |publisher=East Woods Press |location=Charlotte, North Carolina |isbn=978-0-88742-065-8 |page=180 |url=https://archive.org/details/wildflowermeadow0000mart/page/180 |access-date=3 November 2023}}</ref> ''foothills paintbrush'',<ref>{{Cite book |last1=Beaūdoin |first1=Viola Kneeland |date=1983 |title=The Beaūdoin Easy Method of Identifying Wildflowers: Over 475 Mountain Flowers |url=https://archive.org/details/beaudoineasymeth00beau |url-access=registration |location=Aurora, Colorado |publisher=Evergreen Publishing Company |page=29 |isbn=978-0-9611960-0-4 |oclc=10753372 |access-date=3 February 2026}}</ref> ''broadbract paintbrush'',<ref>{{cite book |last1=Pesman |first1=M. Walter |title=Meet the Natives |date=1943 |publisher=M. Walter Pesman |location=Denver, Colorado |page=126 |edition=2nd |url=https://archive.org/details/meetnatives0000mwal/page/126 |access-date=3 November 2023}}</ref> ''wholeleaf painted cup'',<ref>{{cite book |last1=Patraw |first1=Pauline Mead |title=Flowers of the Southwest Mesas |date=1977 |publisher=Southwest Parks and Monuments Association |location=Globe, Arizona |isbn=978-0-911408-47-8 |page=51 |edition=6th |url=https://archive.org/details/flowersofsouthwe0000patr/page/51 |access-date=29 November 2023}}</ref> and ''wholeleaf paintbrush''.<ref name="Flora of CO">{{cite book |last1=Ackerfield |first1=Jennifer |title=Flora of Colorado |date=2015 |publisher=BRIT Press |location=Fort Worth |isbn=978-1-889878-45-4 |pages=566–568 |edition=1st}}</ref>
An older common name is ''painter's brush'', recorded by Alice Eastwood in 1893.<ref>{{cite book |last1=Eastwood |first1=Alice |title=A Popular Flora of Denver, Colorado |date=May 1893 |publisher=Zoe Publishing Company |location=San Francisco, California |page=39 |url=https://archive.org/details/popularfloraofde00eastiala/page/39 |access-date=3 November 2023}}</ref> The Zuni people call ''Castilleja integra'' {{lang|zun|Tsu'yaa'wa tsi'sinakĭa}} in their own language, a compound word which means "hummingbird all sucking-food".<ref name="Zuni Indians">{{cite journal |last1=Stevenson |first1=Matilda Coxe |author1-link=Matilda Coxe Stevenson |title=Ethnobotany of the Zuni Indians |journal=Thirtieth Annual Report of the Bureau of American Ethnology |date=1915 |page=80 |url=https://repository.si.edu/handle/10088/91736 |publisher=Bureau of American Ethnology |hdl=10088/91736 |access-date=2023-11-21 |archive-date=2023-12-04 |archive-url=https://web.archive.org/web/20231204094556/https://repository.si.edu/handle/10088/91736 |url-status=live }}</ref>
==Distribution and habitat== [[File:Castilleja integra - Michael Tidwell 02.jpg|thumb|left|''Castilleja integra'' flowering in Coconino National Forest, Arizona]] The natural range of ''Castilleja integra'' can be broadly defined as northern Mexico and the southwestern United States.<ref name="GBIF">{{cite journal |title=''Castilleja integra'' A.Gray in GBIF Secretariat |url=https://www.gbif.org/species/3170569 |website=GBIF Backbone Taxonomy |publisher=Global Biodiversity Information Facility |access-date=7 November 2023 |doi=10.15468/39omei |date=2022 |author1=Registry-Migration.Gbif.Org |archive-date=7 November 2023 |archive-url=https://web.archive.org/web/20231107220905/https://www.gbif.org/species/3170569 |url-status=live }}</ref> In the United States its range includes Arizona, Colorado, New Mexico, and Texas, but it not found in California or Nevada.<ref name="USDA">{{cite usda plants|symbol=CAIN14 |title=Castilleja integra |date=27 October 2023}}</ref> It also grows in much of northern Mexico including the states of Baja California, Sonora, Chihuahua, Coahuila, Nuevo León, Tamaulipas, and Durango.<ref name="POWO">{{cite POWO |id=801001-1 |title=''Castilleja integra'' A.Gray |access-date=27 October 2023}}</ref><ref name="GBIF" /> The distribution of elevations is quite wide for this species, most often {{Convert|1000 to 3300|m|sp=us}} and they may be occasionally be found all the way down to {{Convert|600|m|sp=us}}.<ref name="FNA" />
''Castilleja integra'' can be found in a variety of wild habitats including open grasslands, dry meadows, Madrean pine–oak woodlands, open pinyon–juniper woodlands, and subalpine meadows.<ref name="Hummingbird" /><ref>{{cite book |last1=Shreve |first1=Forrest |title=The Vegication of a Desert Mountain Range as Conditioned by Climatic Factors |date=1915 |publisher=Carnegie Institution of Washington |location=Washington, D.C. |page=26 |url=https://archive.org/details/carnegieinstitut217carn/page/26 |access-date=24 November 2023}}</ref> They are not typically found in cooler or moist habitats like aspen woodlands.<ref name="Hummingbird" /><ref name="Flora 4corners">{{cite book |last1=Heil |first1=Kenneth D. |last2=O'Kane, Jr. |first2=Steve L. |last3=Reeves |first3=Linda Mary |last4=Clifford |first4=Arnold |title=Flora of the Four Corners Region :Vascular Plants of the San Juan River Drainage, Arizona, Colorado, New Mexico, and Utah |date=2013 |publisher=Missouri Botanical Garden Press |location=St. Louis, Missouri |page=691 |url=https://archive.org/details/mobot31753003888887/page/n708 |access-date=29 November 2023}}</ref> They are at least somewhat fire adapted, a study finding no extirpation in low intensity wildfires and only small amount in moderate intensity fires.<ref>{{cite journal |last1=Stevens |first1=Jens T. |last2=Miller |first2=Jesse E. D. |last3=Fornwalt |first3=Paula J. |title=Fire severity and changing composition of forest understory plant communities |journal=Journal of Vegetation Science |date=November 2019 |volume=30 |issue=6 |pages=1099–1109 |doi=10.1111/jvs.12796|bibcode=2019JVegS..30.1099S |s2cid=201193276 }}</ref>
===Conservation=== NatureServe last evaluated ''Castilleja integra'' in 1986, listing it as apparently secure (G4) at that time. They similarly found it to be apparently secure (S4) at the state level in Arizona, but they did not evaluate the rest of its range.<ref name="NatureServe">{{cite web |last1=NatureServe |title=Castilleja integra |url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.133766/Castilleja_integra_var_integra |website=NatureServe Explorer |access-date=31 October 2023 |location=Arlington, Virginia |date=2023 |archive-date=31 October 2023 |archive-url=https://web.archive.org/web/20231031223345/https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.133766/Castilleja_integra_var_integra |url-status=live }}</ref>
==Ecology== [[File:Castilleja integra - Jeff Birek 01.jpg|thumb|''Castilleja integra'' blooming shortgrass prairie, Elbert County, Colorado]] The variable checkerspot butterfly (''Euphydryas chalcedona'') feeds upon various species in both the Orobanchaceae and Scrophulariaceae families as a caterpillar, including ''Castilleja integra''. The somewhat similar looking leanira checkerspot (''Chlosyne leanira'') is more selective. It is only recorded as eating the paintbrush genus, very often ''Castilleja integra'' in southern Colorado.<ref>{{cite journal |last1=Scott |first1=James A. |last2=Scott |first2=Glenn R. |title=Ecology and Distribution of the Butterflies of Southern Central Colorado |journal=Journal of Research on the Lepidoptera |date=1978 |volume=17 |issue=2 |pages=87–88, 120 |url=https://archive.org/details/biostor-273647/page/87 |access-date=8 November 2023 |location=Santa Barbara, California}}</ref>
Hummingbirds are a frequent pollinator of ''Castilleja integra'' including the rufous hummingbird, broad-tailed hummingbird, and black-chinned hummingbird, due to the good nectar flow,<ref name="Hummingbird" /> each flower producing about 2 milligrams of sugar in its nectar each day.<ref name="Econ Rufous">{{cite journal |last1=Kodric-Brown |first1=Astrid |last2=Brown |first2=James H. |title=Influence of Economics, Interspecific Competition, and Sexual Dimorphism on Territoriality of Migrant Rufous Hummingbirds |journal=Ecology |date=March 1978 |volume=59 |issue=2 |pages=285–296 |doi=10.2307/1936374|jstor=1936374 |bibcode=1978Ecol...59..285K }}</ref> Pollen is deposited by the plants on the bill and crown of the hummingbirds, who are attracted by the nectar reward concealed in the long tube of the flower.<ref name="Hummingbird">{{cite journal |last1=Brown |first1=James H. |last2=Kodric-Brown |first2=Astrid |title=Convergence, Competition, and Mimicry in a Temperate Community of Hummingbird-Pollinated Flowers |journal=Ecology |date=October 1979 |volume=60 |issue=5 |pages=1022–1035 |doi=10.2307/1936870|jstor=1936870 |bibcode=1979Ecol...60.1022B }}</ref> Rufous hummingbirds of both sexes fiercely defend a territory or try to steal a territory of blooming flowers including the orange paintbrush. They try to keep approximately the same number of flowers within the territory and only abandon a territory due to aggression or as the number of flowers decrease.<ref name="Econ Rufous" />
''Castailleja integra'' is considered to be a hemi-parasite, because a host plant is not required for seedlings to sprout and they can photosynthesize to produce at least some of their own energy.<ref name="Compatible Host" /> It is partially dependent on a host plant for healthy growth and in potted tests has been found to not survive longer than three months without one.<ref name="Compatible Host" /> Both the size and the survival of plants is improved when they have a host plant.<ref>{{cite journal |last1=Granados-Hernández |first1=Luisa A. |last2=Pisanty |first2=Irene |last3=Raventós |first3=José |last4=Márquez-Guzmán |first4=Judith |last5=Mandujano |first5=María C. |title=Better alone? A demographic case study of the hemiparasite Castilleja tenuiflora (Orobanchaceae): A first approximation |journal=Population Ecology |date=April 2021 |volume=63 |issue=2 |pages=152–164 |doi=10.1002/1438-390X.12076|bibcode=2021PopEc..63..152G |s2cid=234006080 }}</ref> Known host plants include ''Artemisia frigida'', ''Artemisia michauxiana'', ''Calylophus serrulatus'', ''Ericameria nauseosa'', ''Liatris punctata'', ''Oxytropis sericea'', ''Penstemon pinifolius'', ''Penstemon attenuatus'', ''Penstemon strictus'', ''Penstemon teucrioides'', ''Calylophus serrulatus'', ''Eriogonum strictum'', and ''Eriogonum jamesii''.<ref name="Compatible Host" /><ref>{{cite journal |last1=Mead |first1=Elliott W. |last2=Looker |first2=Michael |last3=Gardner |first3=Dale R. |last4=Stermitz |first4=Frank R. |title=Pyrrolizidine alkaloids of Liatris punctata and its root parasite, Castilleja integra |journal=Phytochemistry |date=September 1992 |volume=31 |issue=9 |pages=3255–3257 |doi=10.1016/0031-9422(92)83487-J|bibcode=1992PChem..31.3255M }}</ref><ref>{{cite journal |last1=Stermitz |first1=Frank R. |last2=Foderaro |first2=Tommaso A. |last3=Li |first3=Yong-Xian |title=Iridoid glycoside uptake by Castilleja integra via root parasitism on Penstemon teucrioides |journal=Phytochemistry |date=March 1993 |volume=32 |issue=5 |pages=1151–1153 |doi=10.1016/S0031-9422(00)95081-7 |bibcode=1993PChem..32.1151S |language=en}}</ref><ref name="Alkaloids" /><ref name="Penstemon">{{cite journal |last1=Nelson |first1=David A |title=Evaluation of Penstemon as a Host for ''Castilleja'' in Garden or Landscape |journal=Native Plants Journal |date=2005 |volume=6 |issue=3 |pages=254–262 |doi=10.2979/NPJ.2005.6.3.254 |jstor=43320529 |url=http://www.jstor.org/stable/43320529 |issn=1522-8339 |access-date=2023-11-28 |archive-date=2023-12-03 |archive-url=https://web.archive.org/web/20231203020608/https://www.jstor.org/stable/43320529 |url-status=live |url-access=subscription }}</ref>
When ''Castailleja integra'' was tested with ''Campanula petiolata'', ''Erigeron elatior'', ''Penstemon virens'', ''Tetraneuris scaposa'', or ''Liatris spicata'' as host plants it had no survival in field plantings after 14 months. When planted with ''Antennaria media'' the rate was 3% and with ''Zinnia grandiflora'' and ''Penstemon crandallii'' it had 17% survival at 14 months. When planted with a host plant in a pot there was 10% or less survival of ''C. integra'' after three months when paired with ''Eriogonum umbellatum'' var. ''dichrocephalum'', ''Gaillardia spathulata'' or ''Geum triflorum''.<ref name="Compatible Host" /> Likewise, silvery lupine (''Lupinus argenteus'') does not support ''Castailleja integra'' very readily, with only one out of forty pairings blooming in a one year test in 2004.<ref name="Penstemon" />
==Uses== ===Cultivation=== Paintbrush flowers are a desirable species in gardens for their showy flowers and attraction of hummingbirds, but can be difficult to grow because of their dependence upon a host species and dislike of being transplanted. This means that plants grown for sale by nurseries must be grown with a compatible host plant in the same pot that will also be desirable to buyers. Orange paintbrush and desert paintbrush (''Castilleja chromosa'') are two of the most tolerant species of garden conditions and being transplanted. The best survival rates for orange paintbrush when planted in pots are with fringed sagebrush, lemon sagewort, rubber rabbitbrush, pine-leaved penstemon, yellow sundrops, Blue Mountain buckwheat, or antelope sage.<ref name="Compatible Host">{{cite journal |last1=Love |first1=Stephen L |last2=McCammon |first2=Tony A |title=Compatible host/parasite pairs enhance propagation of paintbrush ( ''Castilleja'' spp.) |journal=Native Plants Journal |date=2017 |volume=18 |issue=3 |pages=252–265 |doi=10.3368/npj.18.3.252|s2cid=89920217 }}</ref> Among penstemon species, ''Penstemon strictus'' has some of the best survival rates. Distance from the host plant is also a factor, with the survival rate falling by more than 80% when placed at a distance of 4 centimeters instead of just 2 centimeters.<ref name="Penstemon" /> Gardening sources often mention grasses as a host species for paintbrush flowers and ''Bouteloua gracilis'' is recommended by gardening books. Plants rarely survive being transplanted once established, and for this reason they are generally not moved in gardens or transplanted from the wild.<ref name="Native Gardens" />
Orange paintbrush is best suited to unproductive soils, ones without much organic material, that drain very well. They also have proven adaptable to parasitizing species from outside their native range, such as sheep fescue.<ref name="Hitchmough">{{cite book |last1=Hitchmough |first1=James |title=Sowing beauty : Designing Flowering Meadows From Seed |date=2017 |publisher=Timber Press |location=Portland, Oregon |isbn=978-1-60469-632-5 |pages=77, 253, 254 |url=https://archive.org/details/sowingbeautydesi0000hitc/page/77 |access-date=22 November 2023}}</ref> Orange paintbrush will grow in areas as cold as USDA zone 4, minimum temperatures of {{convert|-34.5 to -29|C|F|0}} and as warm as zone 8.<ref>{{cite web |title=Castilleja integra |url=http://navigate.botanicgardens.org/weboi/oecgi2.exe/INET_ECM_DispPl?NAMENUM=2737 |website=Gardens Navigator |publisher=Denver Botanic Gardens |access-date=24 November 2023}}</ref><ref name="Native Gardens">{{cite book |last1=Busco |first1=Janice |last2=Morin |first2=Nancy R. |title=Native Plants for High-elevation Western Gardens |date=2010 |publisher=Fulcrum |location=Golden, Colorado |isbn=978-1-55591-740-1 |pages=84–85 |edition=2nd |url=https://archive.org/details/nativeplantsforh0000busc/page/84 |access-date=29 November 2023}}</ref>
===Traditional uses=== The Zuni people used the root's bark, mixed with minerals, to dye deerskin black.<ref name="Zuni Indians" />
==References== {{Reflist}}
==External links== {{Commons category|Castilleja integra}} *[https://www.inaturalist.org/taxa/160199-Castilleja-integra iNaturalist - Wholeleaf Paintbrush (''Castilleja integra'')] *[https://www.swcoloradowildflowers.com/Pink%20Enlarged%20Photo%20Pages/castilleja%20integra.htm Southwest Colorado Wildflowers - ''Castilleja integra'']
{{Taxonbar|from=Q15349634}}
integra Category:Flora of the South-Central United States Category:Flora of Arizona Category:Flora of Baja California Category:Flora of Coahuila Category:Flora of Chihuahua (state) Category:Flora of Colorado Category:Flora of Durango Category:Flora of Nuevo León Category:Flora of Sonora Category:Flora of Tamaulipas Category:Plant dyes Category:Taxa named by Asa Gray Category:Plants described in 1858