GROWING ROOT CROPS.

New Zealand Herald, Volume LIX, Issue 18244, 10 November 1922, Page 5

GROWING ROOT CROPS.

IMPORTANCE OF MANURINGSOME HINTS: FOR FARMERS. .. The manuring of root crops is an itetn' of vital importance to the modern Istmer. It calls for a certain .amount,, of careful study coupled with" practical, 4*s well as theoretical, knowledge.. Tj> y.':■' "j manure successfully the farmer must, first:', take into consideration the climatic \cc*r>» ditions of the district, the nature of the■-.. ■■■,* soil and tho season in which the «rop' r . is to be sown—whether spring, summer. ._./,..' or autumn. What fertilisers to use. and .. ; how to apply them are subjects which are discussed in bulletins and books by • many authors; but even after studying, ',:'. -_' v \ all the literature, the.farmer &ust expert ment with-his own land and hisvoVnr •"% crops to determine just what materials are most profitable for bio use. A faVmer' who is at all observant may learn a; ; . great deal from his neighbours by study- .. ing the growth of his neighbour's . . ~ ous crops and by obtaining information- ~~~ as to his, or their, methods of manuring. •-.> Referring to literature on tho subject of nva.uring,' the advice as to fertilisera is ,<, , more valuablo in teaching a man principles, in suggesting means of experi- '■> menting and in designating tho probabilities of any lino of actidft, than in spt»cifying just what, fertilisers he should;.'... use. On tho other hand, practical experiments carefully carried out, hi addition to such knowledge as may bo obtained:; from other sources, will prove most use-;., full and aid toward success. :•' . -Experiments in Manuring. A small area on one side of a field may be devoted to manurial experiments, i 0;a different parts of this the various.:;; elements and combinations of manures _ may be applied. The experimenting area ~ need not be at all extensive. A small. .'•■ asa treated each with some artificial or a mixture will suffice for ordinary practical knowledge. Before deciding what manure to use, let us thoroughly understand what we mean by manure. Many do not seem to know,'beyond tho fact ■'.>.., that it is to encourage the growth -of- - 1 . crops.' 'In the first the word' ';' manure, as we understand it in modern agriculture, is applied to any substance • which bv its application contributes to the fertility of the soil. The substances necessary for plant growth, which are apt to be lacking ia a soil are oidy three - x in number—viz., nitrogen, phosphoric ~-~ , ~ acid and potash. A manure, therefore,, is understood to be any substances con- - , ? ; taining these ingredients, either singly or together, and its commercial value is determined by the amount of these in,gredients it contains. The artificial or «,chemical manures are not as a rule allround manures, suited to supply to the soil all the constituents required by crops. Generally speaking, they supply only two'" " '■" * • or three of the constituents required by crops. In order to make -balanced , manures suited to supply all the chief constituents required, cone must ■■*, ■• .-•■.', - fair amount of chemical knowledge, and ....V even then, with this knowledge, we" are '- ; * apt to make mistakes, unless the operator" has practical knowledge of 'the soil in •.'■- which it is to be applied.

Artificial Manures. It is only since artificial manures came into general use that the mixing of manures became of importance. Various | -chemical reactions occur whe&- artificial [manures are mixed together, and some of /, I them, are harmful and cause loss of «f j. -V I able material. Manure i s simply plant }" Sood; plants cannot live without it. A,- * soil may contain all the ingredients 0 f; -; >'ji »■ ' plant food 'required for most <irops; -other soils are'dencieht in one or more of these ingredients. So, if not contained in sufficient quantities in a soil, the ingredients', lacking must be added to form a -+. manure with that already contained in K-/ the soW. A Uttle experimenting as above * stated, together with csre'fid,observations, .'*;,' will in the majority of point out i iJ v to the farmer that which is deficient and. „'. ' that which is in plentiful supply in his soil. When this information is obtained, *■*'■■?. the farmer is in a better to manure his land for the various -.crops,'*;: v. Complete Fertilisers. If the fanner is unable to -determine r* what particular manorial ingredient is Y : deficient in his soil, and as no good result ? can be obtained' from the addition.; "of y ".\ one element unless the other two are, present in sufficient quantity, it is safer to apply complete' fertilisers. Yet "In •"■?!*• sonve cases it is unwise to apply complete "s£■; fertilisers. This is particularly true of %; \> the application of nitrogen. The growih ~.; ; , " may already be so heavy that 4he addi- ' ?/ tiqn of nitrGgen would cause an oyer- 4 •:, growth, and yet the plants may need- ~ ' . fertilising. Nitrogen conduces especially '■'.' K%i to leaf growth. Therefore, it is the most .„ & important element in the fertilising of ,'-■;*«'.'■.'. such crops as ate grown for thfeir leaves,-, as, for instance, rape, kale, cabbage, etc.- .;,!•' v Nitrogen leaches "rapidly, especially if applied in the form of nitrate of or sulphate of anunoria. It is '/.■ moTe suited to sowing with spring-script''&-:"*. *5 crops, and when used in liberal amounts, v " it should be applied at intervals and not ,;' all at once. Phosphoric acid and potash,,, t even if soluble, do not leach badly an '■•'-% a rule, because they tend to form ia- .„ ~ The more vegetable matter a soil con-* •'■ tains the less pronounced is the aclion -\ of leaching. A soil rich in organic matter is therefore less liable to leach soluble compounds with soil constituent*. ~/ than a soil deficient in organic matte*. "'V