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A ne^" nublic;-ition by 31p,ke, Nightingnlo pnd Dnvidson 

 of the Nevf Jersey Agrlcult'irnl Experii.ient Str-^tlon (Bui. 626), 

 "Nutrition of Apple Treves," hpa recently been publinhed. Lepf 

 symptoms of minernl deficiencies .-"■re shovn in natural color. 

 The authors point out that deficiencies of plant nutrients are 

 most likely to occur on li.^-ht sandy or sandy gravelly soils. 

 Even "'here apple trees are planted at optimum commercial dis- 

 tances, the roots "'ill ultimately utilize the entire soil area, 

 if they receive proTDcr culture. Fertilizer and cultural prac- 

 tices, therefore, should be designed to develop or maintain the 

 fertility of the entire orchard area,. 



In addition to the three elements usu'^lly considered 

 necessary for the grovth of a plant, at l^ast eight others have 

 thus far been fou.nd ecoential, r^a folloi'^s: calciu^m, magnesium, 

 iron, boron, sulphur, coppery manganese and zinc. Only minute 

 quantities of the latter minerals are renuired for most plants 

 and the average fertile soil is likely to be sufficiently well 

 supplied. 



An interesting bit of arithmetic is foi,md in bulletin 

 363 of the Missouri Agricultura.l Ex;oeriment St'ition, "Fertiliz,in^ 

 Fruit Trees ^'ith Nitrogen." In one table -"e find the follo'"ing 

 figures v/hich itemize the nitrogen needs o'^ r 20-year-old apple 

 tree. The figures are expressed in pounds of fertil*.zer contain- 

 ing 20 to 21,"^ nitrogen. Nitrogen removed '"ith fruit crop, 2 lbs. ; 

 nitrogen removtid by pruning, .5 lbs.; nitrogen lost from autumnal 

 dropping of leaves, 2 lbs.; nitrogen lost :^rora dropning of flowers 

 and young fruits, .3 lbs.; nitrogen required for ma.intenance 

 (gro^'4;h), 1 lb.; total ^.S lbs. Nitrogen returned to tree from 

 decay of flowers, fruit, leaves, etc., 1.2 lbs. Difference (net 

 requirements to be applied), k-.6 lbs. 



C. L. Burkholder of the Indiana Experiment Station says, 

 "To maintain a desira.ble strav; mulch on mature trees, requires 

 at least 2 ba.les per tree to start '''ith and a bale nor tree there- 

 after. " He sa.y;3 that '"heat straw contains 10 lbs. of nitrogen, 

 oat stra^v, 12 lbs., and rye strav: 9.3 lbs. per ton. In addition 

 to this, tliere is a small amount of phosr)horun and considerable 

 potash. The fertilizer value of straw is therefore from $1.67 

 to $2.7^ ppr ton, ba.sed on fertilizer prices. Stra"; must there- 

 fore be considered as a source of some fertility in addition to 

 its virtues as a mulch in the stabilizing of moisture relation- 

 ships. IncidentaAly^ the fertility tiound up in such organic mat- 

 ter is not made available unless a supply of nltr&tes is available 

 to bring about its decomposition. 



Missouri Bulletin 379, "Pollenation and Fruit Setting," 

 points out four early ser^son '"aves or periods of dropping, In 

 a.pples. While inf oi'*nation as to cauues of those "drops" is in- 

 complete, the first drop is knovm to be that of flowers which lack 

 polienation or are self pollenoited. The second dron of small 

 frraits is evidently due to embryo weakness and poor gro"rth, due 

 to faulty nutrition. The third and fourth drops are comoosed of 

 fruits 1/2 to 1 inch in diameter which fall because of a. poor food 



