The Western Farm Journal furnishes the following figures:

"Mr. H. H. McAfee, of the Iowa Agricultural College, and also now Secretary of the American forestry association, gives the following as results obtained in twenty years with the trees named below:

Thus, actual tests show that cottonwood will make three-fourths of a cord; that even the slow growing black maple will make one-eighth of a cord; while the ash leaved maple (negundo) will make five-eighths of a cord to the tree in twenty years' growth.

The same trees if grown in groves thickly, would probably not make more than half the quantities named, which would in time come nearer to the figures as given above.

The following will, we think, be a safe estimate for groves or broad belts, in twenty years, planted, say four by four feet, and thinned out as their good deserves, to a maximum distance of sixteen by sixteen feet for the fast growing varieties, and eight by sixteen feet for the slower ones :

Cottonwood..................................................................70 cordi.

Ash-leaved Maple........................................................60 "

White Walnut (Butternut)...........................................50 "

White Maple...............................................................44 "

Elm.............................................................................43 "

Honey Locust (GladiUchia).........................................35 "

White Pine.................................................................32 "

Black Walnut..................................:...........................30 "

Black Sugar Maple (nigra)............................................20 " natural History and Science.