CURRENT FIELD WORK.

New Zealand Herald, Volume LXVIII, Issue 20779, 23 January 1931, Page 18

CURRENT FIELD WORK.

SUMMER OPERATIONS. IMPORTANCE OF CULTIVATION. PREVENTING PUNGOID INFECTION Because 111 tilt' nunibei of iiMjx.italii tasks which present them>elves for at leu - tion, January is generally a very busy month on all types of farms. There is one feature comnion lo several ol the most important of these tasks. I his is the fact that once the proper time arrives to carry them out one cannot postpone them and escape poorer ami less satisfactory results. Attention is directed to some of these tasks in a bulletin issued by the fields division and Plant Research Station. Palmerston Notth.

"There is much cultivation work which will require attention." sav.s the bulletin. "The actual doings of farmers provide concrete evidence that many do not undeistand (he full value and importance of cultivation. Cultivation is certainly only one of the links in tho chain of factors which beget good crops, but the point which must not be overlooked is that ii cultivation is the weak link, there is only one thitifi to do to increase the strength of the chain, that is, improve cultiva tion. Suppression o! Weeds. "Svstematic observation has shown that "the free use of high-quality fertiliser and the sowing of the best seed in ample quantities are effective or ineffective according to the efficiency of the cultivation work. An obvious and important result of cultivation is the suppression of weeds. Its value in this connection is groat because weeds so readily vob crops of then supplies of moisture and direct sunlight which are essential to growth. "The greatest harm done by weeds is the cutting off of the crops' supplies of sunlight. When the supply of direct light is cut off crops cannot satisfactorily feed even though plant food is ill the soil in great abundance. A survey of tho methods of those farmers who participate in crop competitions throws an interesting light on the value of cultivation in tho suppression ot weeds, 'llieso fanners fiequentlv grow mangels or carrots after such crops as mangels, carrots or potatoes and obtain splendid yields wlifyn they do so. Such a practice could not bo adopted satisfactorily unless the first crop in the series was made a cleaning crop m fact as well as in name, 'loo often the crops which in theorv are cleaning crops in reality bring about fouling of the land with weeds. Cultivation is the key to the growing of true cleaning crops. Conserving Soil Moisture. " Other effects of summer cultivation, although not so obvious, are at times equally or even more important. One ot these is that it hinders ;hc escape ol moisture hv evaporation from the surface of the soii. When the surface is kept loose moisture escapes from the soil onh through the leaves of the crop. ITence summer cultivation, if carried out early enough, assists in creating reserves of soil moisture which will, prove of value during dry periods. This effect of summer cultivation is of particular moment in, the extensive portion of New Zealand which has an annual rainfall of 35in. or j is of further value because j it brings about soil aeration. This sets tip chemical changes that make it possiblfor crops to obtain essential substances which, without cultivation, could not be used by the crops and which would be in short supply. Summer cultivation is the particular concern of all those farmers who grow such crops as mangels, potatoes carrots and turnips and swedes and similar crops grown in rows wide enough anar- to allow of intortillage. Preparatorv cultivation, as distinct from intertillage, for such crops as swedes which are still to be sown will also call lor attention. Control of Fungoid Diseases.

" notliei- matter which calls tor attention in the summer is spraying tor the control of fungoid diseases, such as blight in potatoes and tomatoes. W hen such sprayin- gives poor results it is due almost always to one or both of two causes. Ihe first is not doing the work at theJ • time, and the second is using meffecti suraving material. . " Spraying is preventive rather than curative. Hence, to get the best esults. it is necessary that it be done before the disease has made it.s appearamt., so that it will liave the smallest possible opportunity of becoming established. Suitable spraying has a distinct ™lue in checking the spread ol disease which . established in portions of a erop, but should weather favourable to such disease obtain for any period, it then becomes exceedingly difficult to prevent serious extension."