First Report of Cladocolea cupulata on Pinus douglasiana and P. herrerai in Northern Mexico

The mistletoe Cladocolea cupulata Kuijt (Loranthaceae) has previously been reported parasitizing pines (Pinus spp., Pinaceae) in central Mexico (3). As of today, reported pine hosts have been Pinus jaliscana Pérez de la Rosa and P. lumholtzii B.L. Rob. & Fernald from the state of Jalisco (1,2). During July 2005, we found this mistletoe parasitizing P. douglasiana Martinez and P. herrerai Martinez along Route 40 in Durango approximately 8 km east of El Palmito (23°35′54″N, 105°50′45″W, elevation 2,000 m). We also found the mistletoe on P. douglasiana along Route 40 at approximately 18 km west of El Palmito (23°27′51″N, 105°49′58″W, elevation 1,780 m) in the state of Sinaloa. Additional populations of this mistletoe were observed along the roadside of Route 40 in the Sinaloa-Durango border region. Infected trees had one to five mistletoe plants on them. Comparing infected hosts with neighboring noninfected hosts, the mistletoe appeared to have no effect on the growth of the infected trees. No mortality associated with mistletoe infection was observed for either of these mistletoe-host combinations. C. cupulata can be distinguished from its closest relatives, C. grahami Kuijt and C. pringlei Kuijt, by its longer, narrower, opposite leaves, parallel venation, and the saddle-like peduncles that hold four flowers (3). The other taxa have predominantly alternate leaves with pinnate venation and lack the saddle-like peduncle. To our knowledge, this is the first report of C.cupulata parasitizing P. douglasiana and P. herrerai and the first report of this mistletoe from the states of Durango and Sinaloa (2,3). Specimens of C. cupulata and host material were collected and have been deposited at the Deaver Herbarium (ASC), Northern Arizona University, Flagstaff (Accession Nos. 79532, 79533, and 79536). References: (1) B. Chazado. Biosphera 1:3, 1990. (2) B. Geils et al. USDA For. Serv. Gen. Tech. Rep. RMRS-GTR-98, 2002. (3) J. Kuijt. J. Arnold Arbor. Harv. Univ. 56:265, 1975.

First Report of Thyronectria austroamericana Canker on Thornless Honey Locust in North Carolina

Specimens from a thornless honey locust (Gleditsia triacanthos var. inermis ‘Shade Master’) with cankers were submitted in May 1999 to the North Carolina State University Plant Disease and Insect Clinic by staff from the North Carolina Zoological Park (Asheboro). Abundant stromata of Gyrostroma austroamericana, the anamorph of Thyronectria austroamericana, were associated with the cankers. A visit to the Zoological Park during August 1999 revealed seven additional honey locust trees with multiple branch and stem cankers and dieback. All infected trees had perithecia of T. austroamericana and/or its anamorph. The fungus is distinguished by the large clusters of yellow-brown perithecia with dark brown tips produced on stromata emerging from lenticels, elliptical muriform ascospores, and sparse ascoconidia (1,2). Ascoconidia form as the result of ascospores budding within the ascus. Other trees of the cultivar are an integral part of the landscaping theme of the African Pavilion of the park, and park staff were concerned about disease spread. Infected trees were 8 years old, and several had evidence of sunscald cankers, a common infection court of T. austroamericana (2). Thornless cultivars of honey locust are popular landscape plants in the central and eastern United States and may be seriously affected by T. austroamericana (2). Apparently ‘Shade Master’ is very susceptible to the fungus and should not be used as a landscape tree, especially where the disease has been reported. This is the first report of T. austroamericana in North Carolina on any host. Voucher specimens have been deposited in the National Fungus Collection, Beltsville, MD (BPI 74693), and in the Mycological Herbarium, Department of Plant Pathology, North Carolina State University, Raleigh. References: (1) E. V. Seeler, Jr. J. Arnold Arbor. Harv. Univ. 21:429, 1940. (2) W. A. Sinclair et al. 1993. Diseases of Trees and Shrubs. Cornell University Press, Ithaca, NY.

Thyronectria balsamea on Abies fraseri in Pennsylvania and North Carolina

In August 1996, several 4- to 6-m-tall Abies fraseri (Pursh) Poir. in Adams County, PA, were found bearing numerous dead branches and/or dead tops. The trees had been severely stressed by being ball-and-burlapped and replanted in 1993. Distinct cankers occurred between the living and dead portions of stems and branches. Associated with these cankers were abundant, reddish-orange, erumpent stroma, each bearing three to 10 similarly colored cupulate ascomata. The latter contained asci bearing two to four large, muriform ascospores that, as they matured, formed large numbers of small ascoconidia, indicating the pathogen was Thyronectria balsamea (Cooke & Peck) Seeler (= Nectria balsamea Cooke & Peck). In September 1996, cankered dead stems and branches from affected A. frasrei Christmas tree plantations in Avery County, NC, were found bearing the same pathogen. This fungus is known on A. bal-samea (L.) Mill. from northern Minnesota east through Canada to northern New York and Newfoundland (2). Funk (1) reported it from A. lasio-carpa (Hook.) Nutt. in (presumably) British Columbia, but gave no details. This is the first report of it in the eastern United States south of northern New York, a considerable extension of its known range, and the first report of it from A. fraseri. Voucher specimens are in PACMA (Pennsylvania State University Mycologica Herbarium, Mont Alto Campus). References: (1) A. Funk. Can. For. Serv. BC-X-222:142, 1981. (2) E. V. Seeler, Jr. J. Arnold Arbor. 21:442, 1940.