Chapter IV. 

 Adaptation of Varieties 



(Consult table, pp. 212-213.) 



Resistance to Cold, Heat, Wet, Drouth, Soils, Insects, Fungi in Grapes 



As a general, if not a universal, law of adaptation of plants to environment, we find that the 

 natives in the environment are better adapted than the exotics. 



The vine is no exception to this law. Let us test the assertion by comparison. 



What species and varieties of grapes resist winter's cold best? Certainly the vines, and 

 vineyard varieties derived therefrom, native in cold regions, known as Vitis 'vulpina (riparia) ; 

 northern section of V. labrusca; V. cordifolia, northern section; V. bicolor; V. cinerea, northern 

 section ; V. rubra. 



Of these, V. vulpina of Wisconsin, Minnesota and Dakota readily endures, without protection, 

 40 to 50 F. But Vulpina of Virginia and North Texas can endure only 15 to 20. 

 The Labruscas of Massachusetts can withstand 20 Q to 25, while those of South Carolina 

 perish in 10 to 25. The Cordifolia of Central Illinois and Ohio (about the northern limit 

 of this species), endures 15 to 25, while the Florida Cordifolia is sometimes killed to the 

 ground in Northern Texas with zero or a few degrees colder. V. bicolor of Southern Wisconsin 

 endures 30 readily, while Norton Virginia of the nearly allied species of ^Estivalis, finds its 

 northern limits about Louisville and Cincinnati. So we might continue with all the species and 

 their varieties. 



The limiting lines of hardiness to withstand cold do not follow the parallels of latitude but 

 the isothermal lines. Hence we have wild grapes in Northwest Texas that readily endure the 

 winters of Massachusetts, and the Vitis Californica, found along Rogue River in Southern Oregon, 

 its extreme northern range winter kills to the ground, when grown at Denison, Texas. The 

 Post-Oak grape of Northern Texas endures the winters perfectly in Middle Ohio, where tempera- 

 ture sinks to 25 sometimes. But when we come to reverse the test, the Massachusetts and 

 Ohio grapes cannot endure the Texas summers anything nearly so well as do the native Post-Oak 

 and Mustang grape. The Concord, that remains vigorous for fifty years in Massachusetts, its 

 native state, survives only 8 to 15 years in Texas with equally good treatment. This brings into 

 consideration another element of hardiness, the power to withstand great or small range of 

 climatic change. In this the general law still holds good. Those species with their varieties 

 native in a region subject to great and sudden ranges of temperature, can endure well, while 

 those brought into such regions from where the range is small, will surfer, as is the case with 

 grapes of Florida or New England brought into Northwestern Texas. Bo.th suffer, while the vines 

 of Northwestern Texas thrive well, both in Florida and New England, so far as resistance to 

 heat and cold are concerned. In other words Northwest Texas plants have a much wider range 

 of climatic endurance than have either those of Florida or Massachusetts. 



No other section of the United States has so great a range of climatic conditions as Northern 

 Texas and Oklahoma. 



This will suffice as to cold, heat, wet and drouth; but we must not fail to observe that some 

 individuals of a species have greater resistive power than others, all developed in the same climate, 

 soil, etc. This fact is seized by the plant-breeder with great avidity, to increase the hardiness 

 of his varieties of same blood and nativity by selection, depending on the law of inheritance to 

 sustain his selections. 



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