SERICEA AND OTHER PERENNIAL LESPEDEZAS 13 



DISEASES 



Sericea is not greatly troubled with diseases or insects. As will 

 be noted under a discussion of American lespedezas (p. — ), seri- 

 cea is free from the rust that is sometimes serious on the American 

 forms and from other serious leaf diseases. A phoma is re- 

 ported to cause a stem blight (37). The cotton root rot attacks 

 sericea the same as other legumes, and this makes sericea of 

 less value in the cotton root-rot area. 



The Japanese beetle in Maryland and Virginia may partially 

 defoliate sericea but apparently it has not seriously injured 

 stands. This beetle has been reported on ornamental species at 

 Moorestown, Pa. 



Various species of locusts (grasshoppers) and caterpiFars have 

 done considerable damage in perennial stands of sericea, and 

 appear to spend their life cycles in the areas; leaf hoppers are 

 numerous; alfalfa girdlers do considerable damage. 



June bug (May beetle) larva may prove to be a serious pest in 

 older sericea stands. They are appearing in vast numbers in 

 certain fields and pastures; apparently feeding on sericea roots. 



WEED COMPETITION 



While sericea does not suppress weeds during its first season it 

 endures weed competition remarkably well. A first year's growth 

 may be small and apparently smothered by crabgrass, but it will 

 come out strong the next season. If, however, a growth of grass 

 knee high or more falls down, the young sericea may be smothered. 

 Such a growth should be cut down before it falls and be removed 

 for hay. A good stand of sericea 2 or more years old will sup- 

 press all summer weeds but will not hold down winter weeds 

 that make growth while the sericea is dormant. The effect of 

 the sericea on associated summer growing plants will depend on 

 the way it is handled. If sericea in a good stand is allowed to 

 grow uncut until fall, crabgrass, Bermuda grass, broom sedge, and 

 other summer weeds will be shaded out effectively. When sericea 

 is cut one or more times, the shading effect will be modified. 

 Broom sedge and Bermuda grass may live under one cutting, 

 and, if the sericea is cut two or three times, the grasses may 

 even outgrow and ultimately crowd out the sericea. Use of a spike- 

 tooth harrow in sericea stubble has reduced weed competition, 

 loosened the soil somewhat, and mixed the surface leaf residue 

 of sericea together with applied fertilizer into the soil. If the 

 stand of sericea is thin, weeds will invade the field more or less. 

 The remedy is to get and keep a dense, vigorous stand. 



A weed that may be a serious menace to sericea is dodder. 

 This is a parasite and covers mostly the upper part of the plants. 

 Dodder may be great T y reduced by cutting for hay, although two 

 or more cuttings may be necessary. 



