46 OPEN AIR GRAPE CULTURE. 



green and hard, and not within seven weeks of reach- 

 ing the same state of maturity. 



" These facts, which might be multiplied indefinitely, 

 sufficiently show the injurious effects of strong winds, 

 and the necessity of protecting vines as much as pos- 

 sible from their destructive consequences." 



But although there can be no donbt as to the evil 

 effects of wind storms, it must be borne in mind that 

 ventilation, and even motion, are essential to the 

 health and growth of the vine. Experiments made 

 by Andrew Knight, show that young trees tied to 

 stakes so as to prevent all motion, do not increase in 

 size as much as those left to the free action 

 of wind. Hence, perhaps, one reason why wire is to 

 be preferred to wood for the cross slats of trellises. 

 In the northern States, however, we in general have 

 wind enough for all useful purposes. But in view of 

 these facts, we would rest content with shelter out- 

 side of the vineyard, and unless in very exposed situ- 

 ations we would not deem it advisable to place either 

 trees or fences amongst the vines. 



But while we can guard against wind and storms 

 by belts of woods or high fences, there are other in- 

 fluences which we cannot thus alter. Chiefly among 

 these is the exposure of the sun's rays. 



Exposure is, in general, derived from one or both 

 of two causes. First, the inclination of the ground, 



