42 BULLETIN - 479, XT. S. DEPARTMENT OF AGRICULTURE. 
WEEDING AND CULTIVATING. 
"Weeding in seed beds is usually a hand operation because the 
seedlings or rows of seedlings are too close together to permit the 
use of hand cultivators. Weeds are most easily removed when the 
beds are moist. They should not be allowed to become so large that 
their removal will disturb the seedlings, but there is no necessity of 
removing them when they are very small. Such work is slow and 
tedious. The removal of weeds improves the growing conditions for 
the stock by eliminating competition for light and soil moisture. 
Cultivation is not practiced extensively in seed beds at Forest 
Service nurseries, except to check damping-off. Broadcasted beds do 
not permit it; and where a good water system is installed it is not 
essential for the purpose of conserving moisture. Watering is effi- 
cient and cheaper. In heavy soils which bake and crust after water- 
ing, however, cultivation is desirable. It breaks up the crust and 
insures a better aerated and warmer soil, a condition which tends to 
the development of larger and better stock. Where the stock is in 
rows 6 inches or more apart, hand cultivators can be used. Im- 
provised rakes with tines of 8d and lOd finishing nails are some- 
times used, but are not very satisfactory. Garden rakes and potato 
hooks with some of the tines removed, or very small hoes, are quite 
effective. 
WINTER MULCHING. 
Some soils are subject to heaving caused by alternate freezing and 
thawing during the winter and spring. When this occurs plants are 
liable to be lifted with the soil and a portion of their roots broken 
off. Thin stands of seedlings and seedlings with shallow root sys- 
tems are most subject to this damage. When the soil resumes its 
normal position the plants remain sticking up above the beds or 
else topple over. It is not a practicable operation to reset them in 
the ground, and they are usually a total loss. Winterkilling due to 
excessive drying of the tops of stock when the ground is frozen and 
the roots unable to secure water is another source of danger. Where 
necessary, then, precautions should be taken to guard against these 
two sources of loss. 
For protection against heaving and winterkilling good, clean straw, 
marsh hay, or leaves and twigs free from seed can be used as a mulch. 
At the Monument Nursery oak brush, cut in August to retain the 
leaves, gives splendid results for winter mulch on yellow pine. A 
cover used with success on the Minnesota ISTational Forest is burlap 
of one thickness. After the first fall of snow of H inches, which 
sifts in and around the seedlings, nearly covering them, the burlap 
cover is put over the beds and secured in place by the edges of the 
seed-bed frames, which are left on the beds over winter. This cover 
