132 FOREST TREES. 
the prairie regions of the West, young wood, princi- 
pally Oak, springs up on the bluffs and broken lands 
along the streams when fires are excluded, and only 
needs protection ultimately to become valuable 
timber. 
In many of the oaks, the form of the leaves varies 
so much with different conditions of the tree or 
different stages of its growth, that it constitutes an 
uncertain characteristic by which to distinguish the 
species. Consequently, where the wood is similar, 
different speeies are sometimes confounded under one 
name. The fructification affords a more certain mode 
of distinction. 
The Oaks are propagated almost exclusively by 
seed, grafting and layering being employed only for 
the increase of particular varieties. The acorns fall 
in October, and should be collected before they 
become dry, mixed with sufficient sand to prevent 
heating, and kept damp in a cool place until sown. 
This may be done in autumn or in early spring. The 
latter is safest, as they are sometimes taken out by 
mice and squirrels in the winter. It seems to be the 
prevalent opinion that it is best to plant the acorns 
where the trees are to remain, though there are not 
wanting those among the tree planters of Europe 
who maintain that itis best to transplant them. The 
best mode of treatment appears to be to plant the 
acorns one foot apart in alternate rows, planting corn, 
potatoes, or beans in the intermediate rows. This 
should be continued for at least three years, after 
which the vacant rows should be planted with Silver 
