First Report of Durangan Dwarf Mistletoe, Arceuthobium vaginatum subsp. durangense, on Pinus cooperi and P. engelmannii in Mexico

The Durangan dwarf mistletoe (Arceuthobium vaginatum subsp. durangense Hawksw. & Wiens, Viscaceae) parasitizes several species of pines (Pinus spp., Pinaceae) in the Mexican states of Durango, Sinaloa, and Jalisco (1,3). This mistletoe has primarily been reported from the western edge of the Sierra Madre Occidental in eastern Sinaloa and western Durango, but its distribution there is not well documented (3). In March 2007, I found Durangan dwarf mistletoe parasitizing Pinus engelmannii Carr., approximately 25 km north of Mexico Route 40 (24°00′51″N, 105°26′48″W, elevation 2,200 m), and on P. cooperi Blanco approximately 90 km north of Route 40 (24°24′40″N, 105°35′26″W, elevation 2,710 m) along the road to San Miguel de las Cruces, Durango. These populations are approximately 50 and 80 km northeast of the closest known population of Durangan dwarf mistletoe west of Buenos Aires along Route 40 in extreme western Durango. Infection of P. engelmannii was severe on 25 trees, but only severe on two trees of P. cooperi. No mortality associated with infection by Durangan dwarf mistletoe was observed at either location. Infection caused large, nonsystemic witches' brooms on P. engelmannii, but no brooms were observed on infected P. cooperi. To my knowledge, this is the first report of Durangan dwarf mistletoe on P. cooperi and P. engelmannii, and the first report of this mistletoe from the central Sierra Madre Occidental (3). Although Hawksworth and Wiens (2,3) treated Durangan dwarf mistletoe as a species (A. durangense Hawksw. & Wiens), I use the earlier classification of Durangan dwarf mistletoe as a subspecies of Mexican dwarf mistletoe (A. vaginatum (Willd.) Presl subsp. vaginatum) (1) because of recent molecular evidence (4) and morphological similarities with Mexican dwarf mistletoe. The principal difference between these mistletoes is that plants of Durangan dwarf mistletoe are bright orange while those of Mexican dwarf mistletoe are dark brown to black (1–3). Specimens of Durangan dwarf mistletoe on Pinus engelmannii and P. cooperi have been deposited at the Deaver Herbarium, Northern Arizona University, Flagstaff (Accession Nos. 76455 and 76456, respectively). References: (1) F. G. Hawksworth and D. Wiens, Brittonia 17:213, 1965. (2) F. G. Hawksworth and D. Wiens. Phytologia 66:3, 1989. (3) F. G. Hawksworth and D. Wiens. USDA For. Serv. Agric. Handb. 709, 1996. (4) D. L. Nickrent et al. Am. J. Bot. 91:125, 2004.

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First Report of Arceuthobium aureum subsp. aureum in Mexico

Plant Disease ◽

10.1094/pdis-91-4-0469b ◽

2007 ◽

Vol 91 (4) ◽

pp. 469-469

Author(s):

R. Mathiasen ◽

B. Howell ◽

G. Garnett

Keyword(s):

Type Locality ◽

Flowering Period ◽

Dwarf Mistletoe ◽

First Report ◽

Northern Arizona ◽

Northern Arizona University ◽

Pinus Spp

The golden dwarf mistletoe (Arceuthobium aureum Hawksw. & Wiens subsp. aureum, Viscaceae) parasitizes several pines (Pinus spp., Pinaceae) in central Guatemala (1). In September 2006, we observed golden dwarf mistletoe parasitizing Pinus maximinoi H.E. Moore in southern Chiapas, Mexico; 1 km west of El Rosario along Mexico Route 211 (15°19′23″N, 92°17′45″W, elevation 1,720m). Golden dwarf mistletoe can be distinguished from the closely related Peterson's dwarf mistletoe (A. aureum Hawksw. & Wiens subsp. petersonii Hawksw. & Wiens) by its smaller shoots, occurrence below 2,200 m in elevation, and flowering period (1). The shoots of the dwarf mistletoe at the El Rosario location were less than 20 cm high and male plants were not flowering. Male plants of Peterson's dwarf mistletoe observed at the type locality and other locations in Chiapas during September were in full flower. Although only 29 trees were infected at this location, infection was severe on 11 trees, but no mortality associated with dwarf mistletoe infection was observed. Mistletoe infection did not induce the formation of witches'-brooms near El Rosario, but infection by golden dwarf mistletoe on P. maximinoi does induce witches'-brooms on older trees in Guatemala (2). The golden dwarf mistletoe population near El Rosario is approximately 150 km west of the nearest known population of this species in Guatemala (1). To our knowledge, this is the first report of golden dwarf mistletoe in Mexico. Specimens of golden dwarf mistletoe from Chiapas, Mexico were deposited at the Deaver Herbarium, Northern Arizona University, Flagstaff (Accession No. 83122). References: (1) F. Hawksworth and D. Wiens. Dwarf Mistletoes: Biology, Systematics, and Pathology. USDA For. Serv. Agric. Handb. 709, 1996. 2) R. Mathiasen et al. Madrono 23:122, 2004.

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First Report of Arceuthobium globosum subsp. grandicaule in Honduras

Plant Disease ◽

10.1094/pdis.2001.85.5.563a ◽

2001 ◽

Vol 85 (5) ◽

pp. 563-563 ◽

Cited By ~ 1

Author(s):

J. Melgar ◽

R. Mathiasen ◽

B. Howell

Keyword(s):

Species Identification ◽

Central Mexico ◽

Dwarf Mistletoe ◽

Stem Base ◽

First Report ◽

Northern Arizona ◽

West Central ◽

Northern Arizona University ◽

Pinus Spp ◽

Brown Color

Large-stemmed dwarf mistletoe (Arceuthobium globosum Hawksw. & Wiens subsp. grandicaule Hawksw. & Wiens-Viscaceae) parasitizes several Pinus spp. in central Mexico and western Guatemala (1). In November 2000 several trees of Pinus hartwegii Lindley were discovered being parasitized by this dwarf mistletoe near the summit of Cerro las Minas, Montana de Celaque (2850 m elevation) approximately 12 km southwest of Gracias, Department Lempira, Honduras. Species identification was based on the size of the plants, which were greater than 50 cm in height, and the dark brown color and size (2.1 to 4.5 cm) of the stem base (1). There was no apparent infection of nearby Pinus ayacahuite Ehrenb., which is known to be immune to the pathogen. Specimens of A. globosum subsp. grandicaule were collected and deposited at the Herbario, Escuela Nacional de Ciencias Forestales, Siguatepeque, Honduras and at the Deaver Herbarium, Northern Arizona University, Flagstaff. To our knowledge, this is the first report of this dwarf mistletoe in Honduras and extends its eastern distribution from west-central Guatemala by approximately 300 km. Reference: (1) F. G. Hawksworth and D. Wiens. 1996. Dwarf Mistletoes: Biology, Pathology, and Systematics. USDA Agric. Handb. 709.

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First Report of Psittacanthus macrantherus on Pinus devoniana and Quercus castanea in Mexico

Plant Disease ◽

10.1094/pd-90-1461c ◽

2006 ◽

Vol 90 (11) ◽

pp. 1461-1461 ◽

Cited By ~ 1

Author(s):

B. Howell ◽

S. Kenaley ◽

R. Mathiasen

Keyword(s):

North American ◽

First Report ◽

Northern Arizona ◽

Infected Tree ◽

Northern Arizona University ◽

Pinus Spp ◽

Very High ◽

Important Parasite

The mistletoe Psittacanthus macrantherus Eichl. (Loranthaceae) is an important parasite of pines (Pinus spp., Pinaceae) in Mexico (1). It has been reported to parasitize Pinus engelmannii Carr., P. herrerai Mart., P. lawsonii Roezl ex Gord. & Glend., P. lumholtzii Robins & Fern., P. oocarpa Schiede, and P. pseudostrobus Lindl. (1). During July 2005, we found this mistletoe parasitizing P. devoniana Lindl. and Quercus castanea Nee near Route 40 in Sinaloa, Mexico approximately 12 km west of El Palmito (23°30′N, 105°07′W, elevation 1,900 m). The mistletoe was common in P. devoniana, and some trees were severely infected (>10 plants per tree). However, no mortality associated with mistletoe infection in P. devoniana was observed. Only one infected tree of Q. castanea was observed in this area and it was not severely infected. We also observed this mistletoe on P. douglasiana Mart. along Route 40 west and east of El Palmito, but no specimens were collected because plants were very high in the crowns of the infected trees. To our knowledge, this is the first report of this mistletoe parasitizing P. devoniana, P. douglasiana, and Q. castanea (1). Specimens of Psittacanthus macrantherus from P. devoniana and Q. castenea have been deposited at the Deaver Herbarium (ASC), Northern Arizona University, Flagstaff (Accession Nos. 79534 and 79535). References: (1) B. Geils et al. Mistletoes of North American conifers. USDA For. Serv. Gen. Tech. Rep. RMRS-GTR-98, 2002.

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First Report of Arceuthobium blumeri on Pinus ayacahuite and A. globosum subsp. globosum on P. durangensis from Sinaloa, Mexico

Plant Disease ◽

10.1094/pdis-94-3-0377b ◽

2010 ◽

Vol 94 (3) ◽

pp. 377-377

Author(s):

S. Quiñonez Barraza ◽

R. Mathiasen

Keyword(s):

New Mexico ◽

San Jose ◽

White Pine ◽

Dwarf Mistletoe ◽

Sierra Madre Occidental ◽

First Report ◽

Northern Mexico ◽

Needle Morphology ◽

Sierra Madre ◽

System 2

Arceuthobium blumeri A. Nelson (Blumer's dwarf mistletoe, Viscaceae) is a parasite of Pinus ayacahuite Ehrenberg ex Schlechtendahl (Mexican white pine) and P. strobiformis Engelm. (southwestern white pine) in the Sierra Madre Occidental of northern Mexico (3). It is widely distributed in Chihuahua and Durango and is known from one location in Sonora (3,4). A. globosum Hawksworth & Wiens subsp. globosum (rounded dwarf mistletoe) parasitizes several pine species in the same areas of Mexico, but extends as far south as northern Jalisco (3). In July 2005, S. Quiñonez Barraza observed both of these dwarf mistletoes in Ejido San José del Barranco, Municipio de Badiraguato, Sinaloa, Mexico. A. blumeri was observed parasitizing P. ayacahuite at two locations: Paraje Faldeo Rancho del Oso (25°39′18″N, 107°01′27″W, elevation 2,600 m) and Paraje La Tableta (25°40′14″N, 107°01′33″W, elevation 2,520 m). The host at these two locations was identified by cone and needle morphology (1). Because the mistletoe plants were gray to straw in color and larger than 6 cm, they were clearly A. blumeri and not A. apachecum Hawksworth & Wiens, another dwarf mistletoe that parasitizes P. strobiformis in Arizona, New Mexico, and Coahuila, Mexico (3). A. globosum subsp. globosum was observed parasitizing P. durangensis Martínez at Paraje Puerto del Alacrán (25°39′52″N, 107°00′57″W, elevation 2,650 m). Infection of the pine hosts was severe at all three locations in Sinaloa and many trees were rated as class 5 and 6 by the 6-class dwarf mistletoe rating system (2). Large witches' brooms were formed on P. ayacahuite infected with A. blumeri, but no witches' brooms were formed on infected P. durangensis. Typically, A. globosum does not induce witches' brooms on infected pines (3). Specimens of A. blumeri and A. globosum subsp. globosum were collected and deposited at the Herbario CIIDIR, Instituto Politecnico Nacional, Durango, Dgo., 34220 Mexico. To our knowledge, this is the first report of A. blumeri and A. globosum subsp. globosum from Sinaloa, Mexico. References: (1) A. Farjon and B. T. Styles. Flora Neotrop. Monogr. 75. 1997. (2) F. G. Hawksworth. USDA For. Serv. Gen. Tech. Rep. RM-78, 1977. (3) F. G. Hawksworth and D. Wiens. USDA For. Serv. Agric. Handb. 709, 1996. (4) R. Mathiasen et al. Madroño 55:161, 2008.

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First Report of Arceuthobium hondurense in Oaxaca, Mexico

Plant Disease ◽

10.1094/pdis.2002.86.1.72b ◽

2002 ◽

Vol 86 (1) ◽

pp. 72-72 ◽

Cited By ~ 1

Author(s):

R. Mathiasen ◽

D. Nickrent ◽

C. Daugherty

Keyword(s):

National Park ◽

Male Flower ◽

Flower Color ◽

Its Sequences ◽

Dwarf Mistletoe ◽

First Report ◽

Northern Arizona ◽

Northern Arizona University ◽

Isthmus Of Tehuantepec ◽

Celaque National Park

Honduran dwarf mistletoe (Arceuthobium hondurense Hawksw. & Wiens) has only been found in four locations in Honduras: west of Zamorano, east of Lepaterique, Cusuco National Park, and Celaque National Park (1,2). At one time it was believed that this mistletoe could be in danger of extinction (1). However, it has also been reported in two locations in Chiapas, Mexico (3). In December 2000, ≈1 km north of Suchixtepec, Oaxaca, Mexico, near Route 175 (elevation 2,770 m), we collected a dwarf mistletoe parasitizing Pinus tecunumanii (Schw.) Eguiluz et Perry that was morphologically similar to A. hondurense (1). This population initially had been classified as A. nigrum Hawksw. & Wiens (1), but is now classified as A. hondurense based on morphology (male flower color and stigma length) (1) and analysis of nuclear rDNA internal transcribed spacer (ITS) sequences from Honduras (GenBank Accession No. AF325969) and Oaxaca (GenBank Accession No. AY055215). A comparison of these two A. hondurense ITS sequences indicated they are very closely related to each other, whereas both are distinct from A. nigrum (GenBank Accession No. L25693). Specimens of A. hondurense from Oaxaca were deposited at the Deaver Herbarium, Northern Arizona University, Flagstaff. To our knowledge, this is the first report of A. hondurense in Oaxaca, Mexico, and extends its known distribution west across the Isthmus of Tehuantepec from central Chiapas by ≈400 km. References: (1) F. G. Hawksworth and D. Wiens. Dwarf Mistletoes: Biology, Pathology, and Systematics. USDA Agric. Handb. 709, 1996. (2) R. Mathiasen et al. Phytologia 85:268, 1998. (3) R. Mathiasen et al. Plant Dis. 85:444, 2001.

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First Report of Arceuthobium vaginatum subsp. cryptopodum on Pinus mugo

Plant Disease ◽

10.1094/pdis.2003.87.11.1395c ◽

2003 ◽

Vol 87 (11) ◽

pp. 1395-1395

Author(s):

R. Mathiasen ◽

M. Haefeli ◽

D. Leatherman

Keyword(s):

Pinus Ponderosa ◽

Ponderosa Pine ◽

Pinus Mugo ◽

Black Forest ◽

Dwarf Mistletoe ◽

First Report ◽

Northern Mexico ◽

Northern Arizona ◽

Positive Identification ◽

Northern Arizona University

Southwestern dwarf mistletoe (Arceuthobium vaginatum (Willd.) Presl subsp. cryptopodum (Engelm.) Hawksw. & Wiens, family Viscaceae) is a serious and common pathogen of ponderosa pine (Pinus ponderosa Douglas ex Lawson & C. Lawson) in Colorado, Utah, Arizona, New Mexico, and northern Mexico (1). In July 2002, this dwarf mistletoe was observed parasitizing a 1.4-m tall mugo pine (P. mugo Turra) in the Black Forest north of Colorado Springs, CO (39°02.118′N, 104°36.028′W, elevation 2,250 m). The infected mugo pine was planted as an ornamental approximately 6 m from a ponderosa pine infected with A vaginatum subsp. cryptopodum. Dwarf mistletoe shoots were produced on the only infected branch observed but this was sufficient for a positive identification of the dwarf mistletoe. Although J. Weir successfully inoculated mugo pine with western dwarf mistletoe (A. campylopodum Engelm.) and lodgepole pine dwarf mistletoe (A. americanum Nutt. ex Engelm.) (2), to our knowledge, this is the first report of a dwarf mistletoe occurring naturally on P. mugo, as well as the first report of A vaginatum subsp. cryptopodum on P. mugo (1). Specimens of A vaginatum subsp. cryptopodum from P. mugo have been deposited in the Deaver Herbarium, Northern Arizona University, Flagstaff (Accession No. 73761). References: (1) F. Hawksworth and D. Wiens. Dwarf mistletoes: biology, pathology, and systematics. USDA Agric. Handb. 709, 1996. (2) J. Weir. Bot. Gaz. 56:1, 1918.

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First Report of White Fir Dwarf Mistletoe on Mountain Hemlock

Plant Disease ◽

10.1094/pdis.2002.86.11.1274c ◽

2002 ◽

Vol 86 (11) ◽

pp. 1274-1274

Author(s):

R. Mathiasen

Keyword(s):

United States ◽

Western United States ◽

Abies Concolor ◽

Dwarf Mistletoe ◽

First Report ◽

Northern Arizona ◽

White Fir ◽

Wilderness Area ◽

Northern Arizona University ◽

Tsuga Mertensiana

White fir dwarf mistletoe (Arceuthobium abietinum Engelm. ex Munz f. sp. concoloris Hawksw. & Wiens) is a serious and common pathogen of white fir (Abies concolor (Gord. & Glend.) Hildebr.), grand fir (A. grandis (Dougl. ex D. Don) Lindl.), and Low's fir (A. lowiana (Gord.) A. Murr.) in the western United States (1). In August 2002, this dwarf mistletoe was observed parasitizing mountain hemlock (Tsuga mertensiana (Bong.) Carr.) growing among severely infected grand fir near the trailhead to Cabot Lake in the Mount Jefferson Wilderness Area, Oregon at 44°34′27″N, 121°43′43″W, elevation 1,340 m. Only 2 of 27 mountain hemlocks observed in this area were infected. One tree had four infections, and one tree had two infections. Several fully developed male plants were found on one of the infected branches of mountain hemlock and were morphologically similar to those growing on the nearby grand fir. Other dwarf mistletoes that commonly parasitize mountain hemlock (Arceuthobium tsugense subsp. mertensianae and Arceuthobium laricis) were not observed in the area. In addition, white fir dwarf mistletoe can be distinguished from these mistletoes by its larger, yellowish shoots (1). Specimens of the mistletoe from mountain hemlock have been deposited in the Deaver Herbarium, Northern Arizona University, Flagstaff. To my knowledge, this is the first report of white fir dwarf mistletoe on mountain hemlock (1). Reference: (1) F. Hawksworth, and D. Wiens. Dwarf mistletoes: biology, pathology, and systematics. USDA Agric. Handb. 709, 1996

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First Report of Arceuthobium hondurense in Mexico

Plant Disease ◽

10.1094/pdis.2001.85.4.444a ◽

2001 ◽

Vol 85 (4) ◽

pp. 444-444 ◽

Cited By ~ 2

Author(s):

R. Mathiasen ◽

D. Nickrent ◽

C. Parks ◽

J. Beatty ◽

S. Sesnie

Keyword(s):

Pine Forests ◽

Nuclear Rdna ◽

Dwarf Mistletoe ◽

First Report ◽

Northern Arizona ◽

Rdna Its ◽

Las Casas ◽

Northern Arizona University ◽

Pinus Tecunumanii ◽

Rdna Its Sequences

Honduran dwarf mistletoe (Arceuthobium hondurense Hawksw. & Wiens) is a rare dwarf mistletoe previously known only from Honduras (1,2). In March 2000 we collected a dwarf mistletoe from approximately 7 km west of San Cristobal de las Casas, Chiapas, Mexico near Route 190 (elevation 2,440 m), which was morphologically similar to A. hondurense (1). This population had initially been classified as A. nigrumHawksw. & Wiens (1). However, our morphological measurements and analysis of nuclear rDNA ITS sequences of A. hondurense plants from Honduras (GenBank No. AF325969) and the plants from Chiapas (AF325970) have confirmed that the Chiapan population is A. hondurense and not A. nigrum. An additional population of A. hondurense was discovered in Chiapas approximately 11 km west of Oxchuc near Route 186 (elevation 2160 m). Both of the Chiapan populations of A. hondurense were parasitizing Pinus tecunumanii(Schw.) Eguiluz et Perry. Specimens of A. hondurense from Chiapas were deposited at the Deaver Herbarium, Northern Arizona University, Flagstaff. This is the first report of A. hondurense in Mexico and extends its known distribution from northwestern Honduras (3) by approximately 500 km. Although A. hondurense has not been observed in the pine forests of Guatemala, it is probable that it also occurs there (1). References: (1) F. G. Hawksworth and D. Wiens. 1996. Dwarf Mistletoes: Biology, Pathology, and Systematics. USDA Agric. Handb. 709. (2) R. Mathiasen et al. Phytologia 36:211, 1998. (3) R. Mathiasen et al. Plant Dis. 84:372, 2000.

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First Report of Arceuthobium hondurense on Pinus tecunumannii

Plant Disease ◽

10.1094/pdis.2000.84.3.372c ◽

2000 ◽

Vol 84 (3) ◽

pp. 372-372

Author(s):

R. Mathiasen ◽

J. Beatty ◽

J. Melgar

Keyword(s):

National Park ◽

East Side ◽

Dwarf Mistletoe ◽

First Report ◽

Northern Arizona ◽

Shoot Production ◽

Northern Arizona University ◽

Pinus Oocarpa ◽

Celaque National Park

Honduran dwarf mistletoe (Arceuthobium hondurense Hawksw. & Wiens) is a rare dwarf mistletoe found only in Honduras (1,2). Thus far, it has been reported to parasitize only Pinus oocarpa Schiede (2). In October 1999, we observed infection by A. hondurense on P. tecunumannii (Schw.) Eguiluz et Perry along the trail to the summit of Montana del Celaque (elevation 1,750 to 1,800 m) on the east side of Celaque National Park, ≈5 km west of Gracias (Department Lempira), Honduras. Infected pines had witches′ brooms, and mistletoe shoot production was common on infected branches. This is the first report of A. hondurense on P. tecunumannii. Specimens of A. hondurense from P. tecunumannii were collected and have been deposited at the Herbario, Escuela Nacional de Ciencias Forestales, Siguatepeque, Honduras, and at the Deaver Herbarium, Northern Arizona University, Flagstaff. References: (1) F. G. Hawksworth and D. Wiens. 1996. Dwarf Mistletoes: Biology, Pathology, and Systematics. U.S. Dep. Agric. Agric. Handb. 709. (2) R. Mathiasen et al. Phytologia 36:211, 1998.

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Southwestern Dwarf Mistletoe, Arceuthobium vaginatum subsp. cryptopodum, Found Parasitizing Picea pungens in Colorado

Plant Disease ◽

10.1094/pd-89-0106b ◽

2005 ◽

Vol 89 (1) ◽

pp. 106-106

Author(s):

R. Mathiasen ◽

N. Marcus

Keyword(s):

Pinus Ponderosa ◽

Ponderosa Pine ◽

Morphological Description ◽

Dwarf Mistletoe ◽

First Report ◽

Blue Spruce ◽

Northern Arizona ◽

Picea Pungens ◽

Voucher Specimens ◽

Pinus Spp

Southwestern dwarf mistletoe (Arceuthobium vaginatum (Willd.) Presl subsp. cryptopodum (Engelm.) Hawksw. & Wiens, Viscaceae) severely parasitizes several species of pines (Pinus spp., family Pinaceae) in Colorado, Utah, Arizona, New Mexico, and northern Mexico, but it has not been reported to parasitize any species of spruce (Picea, family Pinaceae) (1). However, in June 2004, this dwarf mistletoe was observed parasitizing blue spruce (Picea pungens Engelm.) in the Black Forest north of Colorado Springs, CO (39°02.118′N, 104°36.028′W, elevation 2,250 m). The infected blue spruce was planted as an ornamental approximately 4 m from a 16-m-high ponderosa pine (Pinus ponderosa Douglas ex Lawson & C. Lawson) severely infected with southwestern dwarf mistletoe. Mature dwarf mistletoe shoots were produced on five infected branches of the blue spruce. These shoots were compared with a morphological description of southwestern dwarf mistletoe (1) and this was sufficient for a positive identification of the dwarf mistletoe. The other dwarf mistletoes reported to infect blue spruce are Arceuthobium microcarpum (Engelm.) Hawksw. & Wiens, A. americanum Nutt. ex Engelm., and A. douglasii Engelm.; these are all morphologically distinct from southwestern dwarf mistletoe (1). Three of the infected branches formed small (less than 0.3 m in diameter), nonsystemic witches' brooms. All of the infections on the 6-m-high blue spruce were higher than 1 m on the tree. Thus, it is likely that the spruce was infected after it was transplanted. Three other blue spruces were also located within 4 m of the infected ponderosa pine, but these trees were not infected. To our knowledge, this is the first report of southwestern dwarf mistletoe parasitizing blue spruce and the first report of this dwarf mistletoe on Picea spp. Voucher specimens have been deposited in the Deaver Herbarium, Northern Arizona University, Flagstaff (Accession No. 73959). References: (1) F. Hawksworth and D. Wiens. Dwarf mistletoes: Biology, pathology, and systematics. USDA For. Serv. Agric. Handb. 709, 1996.

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