Subanguina calamagrostis and Its Biology in Calamagrostis spp. in Iowa, Ohio, and Wisconsin.

Goto and Gibler (5) r e p o r t e d that nematodes in leaf galls on Calamagrostis canadensis (Michx.) Beauv. near St. Paul, Minnesota, resembled Anguillulina graminophila [= Subanguina graminophila (T. Goodey, 1933) Brzeski, 1981]. Wu (10) descr ibed Anguina calamagrostis Wu, 1967, later renamed Subanguina calamagrostis (Wu, 1967) Brzeski, 1981 (3), as occur r ing on C. canadensis in On ta r io and Quebec , Canada. Calamagrostis canadensis is a c o m m o n grass in low wet prair ies o f the central Uni ted States. Calamagrostis inexpansa A. Gray occurs in similar habitats, bu t is less prevalent . Dur ing 1982-85 , we found S. calamagrostis in C. canadensis galls col lected f rom the Bergman, Crossman, Hayden, Mark Sand, Steele, Stinson, and Williams prair ies in six Iowa counties, and in C. expansa galls f r om Dickenson County, Iowa. C. canadensis galls conta in ing juveni le and adult nematodes were also collected at the Irwin Prair ie just west o f To ledo , l.ucas County , Ohio, and near Por t Wing, Bayfield County, Wisconsin. N o n e o f the locations had ever been cultivated. Fifty galls f rom 1 to 12 mm long (averaging 4.1 mm) and resembl ing the elongated and fur rowed galls described by Goto and Gibler (5) and Wu (10) occu r r ed on abaxial or adaxial leaf surfaces (Fig. 1). Color varied f rom light yellowish-green to tan in young galls to dark b rown in old galls. Pycnidia o f the fungus Dilophospora alopecuri (Fr.) Fr. of ten made old galls appear blackened. New leaf growth of ten occu r red in axils when galls were near nodes. Large galls of ten caused leaves to be twisted and contor ted . Examinat ion o f several galls f rom all Iowa collections indicated that the life cycle was comple ted in J u n e or July when adults, eggs, and juveniles were found in new grass growth. Most adults had det e r io ra ted by mid-August . Young g reen galls found in early Sep t ember were less than 2 mm long and conta ined juveni les but not adults or eggs. Th i r t y galls in ove rwin te red debris f rom