TIMBER GROWING AND LOGGING PRACTICE 27 
They are the ones whose proportion in the stand the owner should 
constantly strive to increase. If they are sold separately and in 
advance of the others, these species not only will decrease in the 
stand but they will gradually be eliminated from it. Other less valu- 
able species such as maple, elm, hackberr} 7 , black oaks, beech, iron- 
wood, and black gum will take possession of the open spaces. The 
low value to-day of much of the woods in this region is due in part 
to the fact that this practice has been followed for years. 
Still another general principle which should be observed is to take 
advantage of logging operations in any type or situation to clean up 
the woods. In other words, this should be the opportunity for getting 
rid of hollow trees ; trees affected with rot or other diseases, killed or 
dying from insect attack, or badly fire-scarred at the base and almost 
certain to develop rot or to become wormy; trees whose tops have been 
broken by storms, lightning, or previous logging operations and 
which will not in consequence develop into valuable specimens ; and 
trees with large spreading crowns which have little or no value at 
present and never will have much value. It may be necessary to dis- 
pose of these trees for little or nothing or even at a financial sacrifice 
to get rid of them, but it will be well worth while to do so. The ax 
judiciously applied is a tool for building up the forest as well as for 
cutting it down. 
Without doubt the general rule of cutting rather evenly and only 
about one-half the volume of trees over the whole area logged will 
have to be modified to assure reproduction of certain species. Ash, 
yellow poplar, and red gum seedlings, for instance, come up propor- 
tionately most thickly on areas which have been cut clean of old 
growth or at least cut very heavily. This suggests the advisability 
of clean or heavy cuttings in patches of an acre or so where old trees 
of any of the three species mentioned occur in the stand in some 
quantity and where the site is favorable for the growth of high- 
quality timber. Conditions are most favorable on good, moist, well- 
drained soils, such as lower slopes, coves, well-drained bottom lands, 
north slopes, and rich bench lands and flats. 
It is recognized, moreover, that in some stands of timber where 
the trees are all old, no longer growing thriftly, and in many in- 
stances defective, the only sensible method to follow in logging 
operations is cut clean and thus put the area in shape for a new 
growth of young vigorous healthy timber. This is the best practice 
on such areas from the standpoint both of the operator and the 
landowner who wishes to grow another crop of timber on the land. 
In the mixed stands of the central hardwood region it can not be 
stated with assurance that any method of cutting will be entirely 
effective in controlling the future composition of the forest. This 
is particularly true of species which require an abundance of sun- 
light, such as yellow poplar, black walnut, red gum, and cottonwood. 
Under old stands of timber there are commonly large numbers of 
seedlings such as maples, ash, and elm which endure considerable 
shade. These are ready to take possession of any openings created 
by the removal of old timber. Some of the light-requiring seedlings 
will come in, but they are often obstructed if not crowded out alto- 
gether by the shade-enduring trees which were there first. It will 
be necessary to thin out the latter to give others their chance. It 
