32 BULLETIN 47l», U. S. DEPARTMENT OF AGRICULTURE. 



Monument Nurseries no shade is gives until after germination is in 

 progress. 



< Hher covers are often given seed beds to conserve moisture. Bur- 

 lap is quite commonly stretched flat across the beds, and straw, moss, 

 or leaf mold to a depth of about an inch is sometimes sprinkled over 

 thorn. Any of these latter coverings must be removed soon after 

 germination commences. For several reasons burlap is the best 

 cover; it can be put on and removed easily; it does not bring weed 

 seed to the bed; it effectually prevents the wind from shifting the 

 surface soil of the beds; it does not mat down and heat; it allows the 

 sun's rays to filter through to warm the soil better than the other 

 covers; and to some extent it protects the beds from birds. Straw, 

 moss, or leaf-mold coverings can not be put on so rapidly nor dis- 

 tributed evenly; they keep the ground cold, thus delaying germina- 

 tion; they often bring weed, seed to the beds; they are likely to be 

 blown off by wind ; and after germination commences their removal 

 can be accomplished only slowly, not cleanly, and scarcely without 

 damage to numerous seedlings, which when first appearing in the 

 beds are quite brittle and easily broken off. Moreover, where this 

 type of cover has been used, damping-off has, at some nurseries, been 

 more serious. 



In the very dry and hot Southwestern States the efficiency of a bur- 

 lap cover for retarding evaporation is increased by covering it with 

 p.bout one-half inch of fine, dry soil. This procedure would be satis- 

 factory only with seed which germinate rapidly and will not, accord- 

 ingly, require additional watering after the cover is put on. 



In localities where the temperature during the germinating period 

 is very high, where it is very windy, or where the seed germinates 

 very rapidly, the Pettis frame with burlap around the sides and 

 full shade on top is a desirable cover; in cooler localities, especially 

 with slowly germinating seed, no cover at all or simply one of bur- 

 lap is preferable, provided in each case the sowing operations are 

 conducted in the spring. In seed beds sown late enough in the fall 

 so that there is no possibility of fall germination, no cover at all 

 for the purpose of preventing evaporation is necessary. Protec- 

 tion against rodents, birds, and the removal of the soil by wind 

 is still necessary, and for this the same methods should be followed 

 as in spring sowing. 



WATERING OF SEED BEDS. 



Immediately after sowing and covering the seed, the beds should 

 be given a thorough watering. This will usually expose seed which 

 have not been covered deeply enough., settle the soil a little more 

 thoroughly, establish capillarity, and furnish the moisture neces- 

 sary to initiate germination. Between sowing and actual sprout- 



