10 
BULLETIN 1288, U. S. DEPARTMENT OF AGRICULTURE 
USE OF CLEAN SEED BEDS 
Tomato leaf -spot is often found in the seed beds in Maryland 
and doubtless occurs at times in such beds in other States. As the 
seed bed is usually made on a well-manured piece of land and located 
in a protected place, it is warmer than in the open field. The 
fungus is therefore able to grow and develop spores much earlier than 
Fig. 5. — Eggplant infected by Septoria lycopersid 
in exposed places. In sheltered open coldframes facing the sun the 
writers have obtained pycnidia and spores of Septoria lycopersid on 
dead tomato stems as early as May 24 at Washington, D. C. The 
fungus is carried on the plants from the seed bed to the field, where 
it spreads and produces an epidemic much earlier than it otherwise 
would. Much heavier losses therefore result from its early develop- 
ment. 
