A Review Of Haymaking

Press, Volume CIV, Issue 30823, 7 August 1965, Page 10

A Review Of Haymaking

'THEORETICALLY, the con--1 servation of grass in the form of hay is a straightforward proposition. First, grow a desirable species or combination of species, and grow it well. Then let it reach the desirable stage of maturity, cut it, reduce the moisture content to a safe level quickly and store it until required for use. Translating theory into practice, without losing quality and quantity, is a different proposition altogether. Of the methods employed to do this, it is almost true to' say “there’s nothing new under the sun,” because most methods have been tried before, at some time or another. Hay has been made for a very long time and the difficulty of drying and retaining quality has long been appreciated. The first reference in literature to artificial drying using forced air and supplemental heat was in 1869 nearly 100 years ago. Main Advances The main advances in the last 20 years have been technological. New machinery has been produced which enables established principles to be implemented with greater precision and rapidity. The majjrity of current research, involving the use of new equipment, confirms many of the well established principles which formerly were difficult to employ on a large scale because of the lack of suitable mechanical aids. Gras? cut for hay has a moisture content of between 77 per cent and 84 per cent (wet basis) depending on variety, climate, time of day. dew etc. It is living when cut and the normal vital processes are still active until the moisture content has been reduced to 35 per cent to 40 per cent. Until this stage has been reached dry matter loss will occur, and the longer drying takes — whether in sunshine or shade, the greater will be its loss. From this point to the stage where it can be safely baled (below say 25 per cent) is the most difficult for moisture extraction.

Although no further dry matter loss occurs, nutritive losses will become significant

the longer the hay is exposed. Should drying conditions deteriorate, or rain occur, these losses may be substantial. Basically then, there is need for haste in drying—to keep both dry matter loss and nutritive losses to a minimum. Artificial drying fits into this pattern very neatly. In its most economic form, artificial drying is used to extract only the last of the moisture from the crop. Full advantage should be taken of natural drying conditions and field treatments to reduce the moisture content to around 35 per cent to 40 per cent. This can be done in one to one and one-half days, so the weather risk is virtually eliminated. When this hay is baled, clover or lucerne leaves are still tough and firmly attached to the stems

so no cracking or fragmentation occurs as is the case when field-dried crops are baled. When these bales are later fed out the absence of dust and fragments, with their subsequent loss on the ground or in the wind, is most noticeable. This feature alone must have a considerable influence on the reduction of nutrient losses, since lucerne, for example, when cut at the correct stage consists of about 57 per cent leaves.

Logical

Hay cannot afford to be a highly priced commodity or it will be ousted by other forms of conservation or supplementary cropping. If it is to be used as a production ration it can carry the increased cost of artificial drying (around 30s per. ton) but for general maintenance purposes the logical approach is to improve field curing methods to reduce losses and still end up with hay at an acceptable cost (To be continued)

CThis is the first of a series of articles on haymaking methods and equipment based on an address to this year’s Massey University sheepfarmers’ meeting by Mr M. W. Cross, of the university staff.)