AUOOBT 20, l*li. 



The Florists' Rev^ 





ADAPTATION 

 <^ OF PLANTS TO SOILS 



I HE GEEATEST advance in 

 knowledge concerning the 

 adaptation of crops to soils 

 has been achieved through 

 practice and experience 

 rather than by means of 

 field and laboratory studies 

 A the soil. There are many conditions 

 iside from the surface texture which 

 iJay a part in this adaptation, such as 

 the nature of the substratum, depth of 

 water table, etc.; and some insight into 

 the subject may also be had by study- 

 ing the distribution of plants as given 

 in any flora. "Where a region has been 

 settled for many generations, and de- 

 forestation and agricultural practices 

 have been carried on extensively, we 

 find many changes in our soils and con- 

 sequent modification of the flora. Some 

 of the many factors determining the 

 distribution Of plants are complex and 

 difficult to eliminate from 

 other factors, and at pres- 

 ent not enough is known 

 about them to determine 

 their real significance. 



Soil Chajiges. 



An address by Prof. George B. Stone, of Am- 

 herst, Mass., before the Society of American 

 Florists, at the Boston convention, August 20. 



remain viable only a few days or weeks, 

 while others will do so for ten to twen- 

 ty-five or more years. Seeds with a 

 limited term of viability must there- 

 fore find suitable conditions for ger- 

 mination during this time, while the 

 others can afford to await their oppor- 

 tunity. 



Moisture Plays Fart. 



Most garden seeds require a minimum 

 of two to three per cent of soil moisture 

 to germinate at all, and for the best 

 germination a higher percentage is re- 

 quired; therefore during dry seasons 

 the seeds of some crops fail to catch. 

 Purslane and pigweed seed, however, 

 will germinate with a small amount of 



Ou soils which only a 

 half century ago supported 

 certain types of vegetation 

 we now find an entirely dif- 

 ferent flora owing to 

 changes in the nature of 

 the soil, lack of humus con- 

 tributing largely to this 

 modification. Some plants, 

 such as the Canada thistle, 

 were more common forty 

 years ago in some locations 

 than at present, while some 

 other plants which have 

 been growing for some time 

 under cultivation have re- 

 cently escaped and become 

 pests. It would naturally 

 be supposed that this is due 

 to a change in the environ- 

 ment, such as soil conditions 

 or source of seed. But 

 whether there is in plants, 

 as in races of men, a tend- 

 ency to aggressiveness which 

 sometimes unaccountably breaks out al- 

 though usually lying dormant, we will 

 uot venture to say; still there is lome 

 •'\ idence to support such a theory. 



^ome plants are confined to bogs, 

 ^I'lne to sandy soils, and others to heavy, 

 " "inpact soils, and many are adapted to 

 '» great variety of conditions. Others 

 !"« limited to salt marshes, and still 

 •others to territory within a few miles 

 •^^ the seacoast. Elevation, humus and 

 ''""I moisture play an important role in 

 I'lnnt distribution, and some plants are 

 ''■^^tricted by what is termed "seed 

 i:il)it, " the seeds of certain species re- 

 '•' "ling their germinating capacity for 

 ^""le time and others for only a few 

 ^^'■I'ks or even days. For instance, the 

 '"''"'Is of the willow, poplar, alder and 

 "tticr species native to wet locations 



A COMPLIMENT TO THE TRADE 



"The highest conception of intensive 

 horticulture has been realized by florists 



and market gArdeners, and one reason 

 why they do not receive more help from 

 the experiment station is because their 

 knowledge of plants and handling them 

 far exceeds that of the men devoting 

 their time to scientific research. When 

 these workers begin to realize the great 

 degree of skill possessed by the florists 

 and market gardeners, perhaps they may 

 be able to suggest some ideas that will 

 be of value." 



soil moisture and flourish when more 

 desirable plants will not; therefore dur- 

 ing periods of drought we find purslane 

 overrunning gardens and pigweed com- 

 pletely monopolizing newly sown lawns. 

 The percentage of air in soils plays 

 its part in plant adaptation, as do also 

 the chemical constituents and biological 

 characters. The soil texture or mechan- 

 ical properties, which are inseparably 

 connected with the air and moisture of 

 the soil, together with the capillarity, 

 etc., are also important factors in crop 

 production and plant distribution. It 

 should be stated, however, that the spe- 

 cific effect on plant distribution of any 

 one of the factors mentioned is not 

 known; still, a great deal is known con- 

 cerning the effects of chemical constit- 

 uents on plants, much more study hav- 



ing been given to this subject. Soil 

 differs materially in its chemical com- 

 position and mechanical properties, and 

 the configuration of the plant is greatly 

 modified by the different types. Even in 

 a small territory there are characteristic 

 variations in the soil which are of suffi- 

 cient importance to justify specializa- 

 tion in farming. 



Lettuce Soils. 



The river valleys furnish typical soils 

 adapted to the growth of special crops, 

 the meteorological conditions of these 

 localities also emphasizing the -individ- 

 ual character of the crops. The coarse 

 and more friable soils of the Atlantic 

 sea coast (truck soils) are light and 

 porous and are used largely for such 

 market garden crops as lettuce, cucum- 

 bers, tomatoes, radishes, etc. The soil 

 characteristic of the Boston district is 

 admirably adapted to truck 

 farming, being quite loose 

 and easily worked. It is 

 especially adapted to head 

 lettuce, which is grown 

 more skillfully and success- 

 fully in that region than 

 anywhere else. It is char- 

 acterized by a predomi- 

 nance of the coarser parti- 

 cles and a relatively small 

 amount of the finer ma- 

 terials such as silts and 

 clay. Except in some few 

 localities the interior soils 

 are not well adapted to the 

 growth of head lettuce; 

 therefore the curly or open 

 type is grown in the heav- 

 ier and more compact soils 

 of the middle west. In all 

 its stages head lettuce re- 

 quires a loose textured soil 

 for perfect development. 

 These soils are manured 

 heavily year after year, and 

 in the greenhouse are never 

 changed, and the large 

 amount of organic matter 

 furnished by the decom- 

 posed horse manure renders 

 the soil even better adapted 

 to this particular crop. 



A more compact soil, such as that of 

 the Connecticut valley, is characterized 

 by the large amount of fine sand and 

 silt. This soil has long been devoted to 

 the growth of tobacco, onions and cu- 

 cumbers and, to some extent, melons. 

 It contains little organic matter, since 

 commercial fertilizers are use<l entirely. 

 The soil may even vary somewhat in 

 its texture in a limited region, and this 

 variation will alone affect the quality 

 and value of a tobacco crop to a con- 

 siderable degree, and onions to a less 

 extent. The warmer, coarser textured 

 soils are well adapted to melon culture, 

 the crop growing vigorously and matur- 

 ing early, with less liability to infec- 

 tion from blights, etc. 



Asparagus is grown largely in some 



