580 



FERTILIZATION 



{^, Fig. 816) fuses with the nucleus of the egg ( 9, Fig. 

 816), and fertilization is complete. The other, hereto- 

 fore supposed to he disorganized, is now said to fuse 

 with 'the endosperm nucleus {e. Fig. 816). The fer- 

 tilize'd egg hegins at once to grow and forms the em- 



816. Part of an ovule of Lilium Philadclphicum. 



Cut lengthwise; i, r, inner integument, enclosing, except 

 at .1 narroworilice wliere the pollen tube, 7;^, enters, the 

 body of the ovule, which is chietly occupied by the 

 large embryo sac £. A, antipodal end of embi-yo 

 sac witli three nuclei, one much <Usorganized. e, the 

 endosperm nucleus, just being formed by fusion of 

 two nuclei from the respective ends of the embryo 

 sac. d", male nucleus, which has just migrated from 

 pollen tube and is about to fuse with ?, the egg 

 nucleus. The synergidas have disappeared. Magni- 

 fied 670 diameters. 



bryo, while the endosperm nucleus divides and forms 

 cells in which food may be stored for the embryo when 

 it resumes growth at the time of germination. 



Chakles Eeid Baknes. 



FERTILIZERS. There is one fact that has been 

 fairly well established by experiment and inquiry, 

 namely, that fruits, flowers and vegetables are benehted 

 by the intelligent application of manures and fertilizers, 

 and that, in the majority of cases, sucli application is 

 followed by profit. In the first place, these crops shoiild 

 be classified for purposes of fertilization according ti» 

 their period of growth, the first class including the peren- 

 nial fruits and flowers, and the second, the annual flowers 

 and vegetables. Those of the first class differ from or- 

 dinary crops in tliat a longer season of preparation is 

 required, during which time the growth is vegetative 

 rather than productive, though upon this vegetative 

 growth depends the quality and value of the fruit or 

 flower obtained. The growth of both tree and frviit is 

 dependent, too, not only upon the food acquired during 

 its year of growth, but also upon that previou.sly ac- 

 quired, and which has been stored up in bud anil 

 branches. 



The tree fruits include apples, pears, i>eaches, plums, 

 cherries, apricots, etc. It may be regarded as a safe 

 assumption that the fertility elements, phosphoric acid, 



FEKTIJ^IZERS 



potash and lime, contribute materially to the proper 

 growth and hardening of the wood, as well as the matu- 

 ration of the fruit. The necessity for added nitrogen 

 is, on the whole, much less ; it should be applied as 

 the need for it appears in the lack of vigor of the tree. 



In the next place, it is safe to assume that the mate- 

 rials which furnish these elements or constituents in 

 slowly available forms are liable to be quite a.s useful, 

 except under special conditions, as those which nrt 

 quickly available, because the tree growing continuous!} , 

 though slowly, is able to obtain from the gradually dis- 

 solving substances a sufficient amount for its daily 

 needs. Hence, as a rule, fertilizers for fruit trees may 

 include the less available and cheaper forms of con- 

 stituents. 



Apples and Pears. — On soils of good natural char- 

 acter, the fertilization of apples and pears need not be- 

 gin until the trees reacli the bearing period, when an 

 annual dressing of 400 pounds per acre of either of thc 

 foUowing mixtures should be applied in early spring, 

 and plowed in : 



JVo. 1. — One part, or 100 pounds each, of ground bonf, 

 acid phosphate and muriate of potash. 



jYn.i?. — One and one*half parts, or 150 pounds, uf 

 ground bone, and one part, or lUO pounds, of muriate of 

 potash. 



As the trees grow older, these dressings should be in- 

 creased. While no definite rules can be laid down as 

 to the most profitable amounts to apply, the best growers 

 find that for mature trees it pays to use from 1,000 U> 

 1,500 pounds annually. In many cases nitrogen, in 

 additiou to that contained in the mixture, should be 

 used, the kind and form depending, perhaps, upon the 

 relative cost more than upon any other one thing, the 

 minimum amount to be 20 pounds per acre, or an equiva- 

 lent of 125 pounds of nitrate of soda. In many cases it 

 is possible to obtain the necessary nitrogen from tlio 

 growing of leguminous crops, as crimson clover and red 

 clover, though when these are used they should be 

 plowed down early in the spring, in order that their 

 growth may not interfere with the growth of the tree. 

 If they are allowed to remain until mature, they absorb 

 not only the food that may be necessary for the growth 

 of tree and fruit, but the moisture also, and thus they 

 frequently injure rather than improve the crop pros- 

 pects. On poor soils, the necessity for fertilization is 

 naturally greater. In fact, on these liberal fertilization 

 — 500 pounds per acre — should precede the setting of 

 the trees, and be continued annually. On these soil.>^, 

 too, green manuring, as a source of nitrogen, can be 

 practiced with safety for a longer period than in thv 

 preceding case. 



Peaches. — Peaches differ from apples and pears in re- 

 spect to fertilizing. The demands for added plant- 

 food are proportionately greater in the early life of the 

 tree, and are different because of their more rapid 

 growth, their early bearing, and the exhaustive charac- 

 ter of the crops. On soils of good natural character. 

 however, the necessity for fertilizing is seldom apparent 

 until after the first or second year of growth. That is. 

 good soils will provide sufficient food for a normal de- 

 velopment of leaf and wood, and any additional fertili- 

 zation would have the tendency to unduly increase the 

 tree growth. On medium and poor soils, the setting of 

 the trees should be preceded by a fertilization, prefer- 

 ably broadcast in spring, and plowed in, with one or the 

 other of the mixtures recommended for apples and 

 pears, as follows : 



JVo. l.~One part, or 100 pounds each, of ground bone, 

 acid phosphate and muriate of potash. 



JVo. k!. — Om' and one-half parts, or 150 pounds, of 

 grttund bone and one part, or 100 pounds, of muriate of 

 potash. 



On the better soils, No. 2, and on the poorer, No. 1. »t 

 the rate of 400 to 000 pounds per acre, which should be 

 followed by the application of the more soluble fertili- 

 zers, immediately the trees begin to bear. The need of 

 nitrogen is often very marked, and is shown by a lack 

 of vigor of the tree. Nitrate of soda applied broadcast 

 in early spring has proved a very valuable form of ni- 

 trogen, since it is apprt>priated by the roots during the 

 early season, and if a sufficient abundance of the min- 

 erals is present, it enables a normal development of 



