1S39] 



FARMERS' REGISTER. 



145 



and which, if not corrected, must coiUiiiue to ope- 

 rate as (he most powerful discoiira^emRrit toettbrt 

 here. But, if it he true, and admit led, that we 

 actually have a belter silk-climate tliar. any part 

 of Europe, then new and also the stronirest induce- 

 ments will be held out to our countrymen to com- 

 pete with Europe in a contest in which nature 

 is our ally. 



Great as are the transition.?, and remote as are 

 the extremes of lemperaiure, felt ever}^ year in 

 Virginia, and however unfavorable they may be 

 to our comfort, or even to health, they are not of 

 the kind to affect silk-culture injuriously to half the 

 extent that is done b}^ the smaller variations of the 

 milder climate ol Europe. This seemin^I contra- 

 diction will be explained. When winter has once 

 set in, and vegetation is thereby made dormant, 

 no degree of cold known in Virrrinia is sufficient 

 to damage the m ist tender of the mulberr}' tribe. 

 And, indeed, theseverity of thecoklerspellsserves 

 as a safe-ffuard against the trees (stimulated as 

 they would be by continued wirm winter weath- 

 er,) putting forth leaves with the first impulse of 

 spring, and thereby incurring great risk of the too 

 forward leaves being nipped by late spring Hosts. 

 This danger, as has been shown on the authority 

 of Young, and as may be gathered from every 

 French work on silk-culture, is very great in the 

 milder and more temperate climate of France ; 

 and it may be inferred, (i-om the operation of hke 

 causes, that the same danger, though in a less de- 

 gree, must also belong to the silk resrion of Italy. 

 The vicinity of the greater part of all the silk re- 

 gion of these countries to either the Alps, the 

 Pyrenees, or the Appenines, and the consequent 

 frequent exposure to piercing cold winds cominnj 

 from these snow-capped mountains, must much 

 increase the danger of late spring, or summer 

 frosts. On this account, after the leaves of the 

 mulberry trees have started, and still more after 

 the silk-worm eggs have been hatched, a sudden 

 depression of temperature, though but of 20 de- 

 grees, yet if serving to cause frost, might be de- 

 structive to the crop ; when a variation of 40 de- 

 grees in this country would, in comparison, be 

 harmless. The important difi'erence in the two 

 different climates is this. Moderate as may be 

 the variations in Europe, the range of the ther- 

 mometer will ot^ten be found from enough above the 

 freezing point to urge vegetation to put forth, to 

 as much below it as will serve to kill the vegeta- 

 tion so produced. Here, with far greater varia- 

 tions and extremes of temperature, our mildest 

 winter weather is too cold, or the warm spells of too 

 short duration, to permit the mulberry leaves to 

 spring prematurely; and in latter, sprinu and sum- 

 mer, there is no weather cold enough to hurt them. 

 The winter transiiions here are between mode- 

 rately and excessively cold weather ; those of Binn- 

 mer, from moderately to excessively warm. But 

 the mean temperature of the cold season is low 

 enouiil-i to keep vegetative life suspended, and 

 therefore salt?; an 1 the temperature of the warm 

 season is always high enough for the safi'tyof the 

 mulberry leaves afier they have opened and be- 

 gun to grow. It will be readily perceived that the 

 very great and sudden and unpleasant fluctuations 

 of temperature, which constitute the <rreat and ac- 

 knowledged deli^ct of the climate of Virginia, are 

 not inconipatible with enough of steady cold wea- 

 ther in winter, and steady warm weather in sum- 

 VoL. VII— 19 



mer, to make a far better silk-climate than that of 

 a country the most blessed in mild and regular 

 temperature. There is not sufficient distinction 

 usually drawn between a climate being considered 

 warm lor its winter or its summer temperature. 

 The south of France bears in safijty the pome- 

 granate, the olive, and the orange, none of which 

 can grow in open culture, in Virginia ; and hence 

 it would be supposed that the Ibrmer region is 

 much the warmer. But it is the mildness of the 

 winters, which prevents their being killed by in- 

 tense cold, and not the greater or more regular 

 heat ol' the summers, that sustains the life of those 

 trees. And it is not warm winters, but the reverse, 

 if connected with warm summers, which are re- 

 quired ibr the greatest success of mulberry and 

 silk-culture. 



A strong support to the position just staled is 

 presented in an account of the causes of failure of 

 the silk crop in the department of Gard, which 

 reaches to the Mediteranean, and is in the south- 

 eastern part of Languedoc, and in the warmest and 

 best silk region of France. This article is in a 

 French periodical, and though long in our pos- 

 session, had not been read, or supposed applicable 

 and useful here, until this essay had been written. 

 A translation of the article will succeed this; and 

 the reader Vv'Ill there find fully di^^played the dis- 

 advantages of warm weather in winter, as well 

 as of cold weather in spring and summer after- 

 wards. Admit to the full extent the intelligent 

 author's proposition, that the unusual warmth to 

 which the eggs were exposed in winter injured 

 the vitality and health of the worms, and that the 

 Tiite frosts cut off the supply ol food fVoui the too 

 early hatched worms — and still there remains a 

 manifest remote or earlier cause of these imme- 

 diate cause? of fiiilure, viz: the warm weather of 

 winter having stimulated and forwarded the ve- 

 getation of iiie mulberry trees, so as to expose the 

 leaves to be killed by the late spring frosts after- 

 wards. A much colder winter wouUl have great- 

 ly protected the trees, by keeping vegetation inac- 

 tive, even if it had not entirely prevented the 

 evils of the temperature of the succeeding spring. 

 And both a cold winter and a hot spring and 

 summer, (or the usual degrees and variations of 

 temperature in Virginia,) would have been a cer- 

 tain safe-guard against all the lopses which occur- 

 red in this, the warmest part of l'"'ranpe. 



The vigorous growth of the most valuable of all 

 grains, Indian corn, may serve as an indication of 

 the summer climate most fiivorable to silk-worms. 

 This plant requires much heat of surwmer, and of 

 sufficient duration to perfect its growth, and is 

 not affected by the intense cold which may reign 

 ! in winter. And it will neither flourish nor ripen 

 in a climate of much more elevated mean tempe- 

 I rature, but of which the heat of summer and the 

 i cold of' winter are less remote. Thus, while this 

 ! grain grows in the highest vigor and luxuriance, 

 I not only in the longer summers of Virginia, but 

 I under the very rigorous climate of New England, 

 i and even in Canada, where the winter lasts near- 

 ly half the year, yet in Europe it is no where 

 so productive, not even in the olive region ; and 

 cannot be raised to profit where the mean tempe- 

 raiureismuch warmer than that of Virginia. Our 

 cold winters are merely not hurtful to the culture 

 and [iroduol of Indian corn ; but for mulberry and 

 silk-cuUure they are decidedly and greatly advan- 



