RELATION OF EARLY MATURITY TO HARDINESS IN TREES. 227 



the young tree grows more vigorously and grows later in the fall 

 than the old one. 



In Nebraska, peach trees are rarely planted on low ground, but 

 are put on hillsides or on high land. Our planters have learned 

 from experience that peach trees will not survive our winters on 

 low land, or if the trees survive the fruit buds will be killed. Now, 

 it may be a little colder in low places than on high sites, but low land 

 is not usually so much exposed to the cold winds of winter as high 

 land. The real reason why peaches winter-kill in low protected 

 places is that they grow too late in such situations and do not mature 

 their wood properly before winter comes on. 



At the Nebraska Experiment Station, we have a very interesting 

 collection of black walnut trees from seed grown in various localities, 

 from Florida to Canada and from Vermont to California. The 

 trees from northern seed stop growing long before those from 

 southern seed. The trees from South Dakota seed, one fall, were 

 bare of leaves nearly a month before California and Oklahoma trees 

 shed their leaves. The Nebraska trees were not far behind, but the 

 trees from seed obtained from North Carolina, South Carolina and 

 Georgia shed their leaves in readiness for winter after the Nebraska 

 trees had been ready a month and the South Dakota trees had been 

 waiting six weeks. But the important thing for us is the fact that 

 the trees from northern seed, and the trees that ripen their wood 

 early, have never been injured by any winter since the seed was 

 planted, some nine years ago. The trees from southern seed on the 

 other hand, the trees that grow late in the fall, have killed back some- 

 what even in the moderate winters, and in several winters some of 

 them have been killed nearly to the ground. 



Now how can we make use of this relation between early matu- 

 rity and hardiness? In the first place, we can select hardy varieties 

 by choosing the ones that ripen early. In the case of new varieties 

 received for trial^ or in testing seedlings, we can tell fairly well from 

 the behavior of the trees during their first and second years in the 

 nursery whether they will prove hardy or not. Just plant the apple 

 seedling or grafts of the new apple along with a few Whitney, 

 Oldenburg, Wealthy, Ben Davis and Grimes' Golden, note carefully 

 during summer and fall the time the growth stops in case of the 

 new variety as compared wath the standard varieties, and you have 

 at once a fair idea of how hardy your new sort is. 



We can apply the same tests in a way to forest tree seedlings, 

 but it is not so important with them. In getting seed for forest 

 trees or, in fact, any tree or shrub that comes true from seed, get 



