WITH OR WITHOUT A NURSE CROP?
The practice of sowing a nurse crop with alfalfa was inaugurated when the nature of the plant was not as well understood as now. It was also somewhat on the theory too that “a half-loaf is better than no bread.” It began when there was a good deal of doubt about “getting a stand,” and the farmer thought no doubt that a crop of oats or barley would pay for the plowing even if the alfalfa failed. While the practice is continued by many, the prevalent later method is to provide no nurse crop. Few who have abandoned the nurse crop have returned to it. The alfalfa plant does not need protection from the sun, nor is it bettered by dividing any of the soil moisture or fertility with those of another crop. On the other hand, if alfalfa is sowed in the spring, it is important that it obtain an early start in order that its roots can quickly work their way down into the moisture of the subsoil, against the dry days of July and August. When a nurse crop of any vigor is removed the alfalfa plants are likely to be found weak, spindling and with little root growth; the nurse crop also has taken up some of the soil nitrogen needed by the young alfalfa; or if the nurse crop is heavy and has lodged, there will be left bare spots, where the alfalfa has been smothered out.
Cutting the nurse crop is likely to be attended with no little damage to the tender alfalfa plants by trampling their crowns into the ground, or by breaking them off. Practically all the experiment stations favor sowing alone. With few exceptions the second and third years have brought heavier yields where no nurse crop was used. The theory that the nurse crop will prevent the weeds choking the alfalfa is apparently, as a rule, not well founded. In the first place alfalfa should not be sown on foul land, and in the second place proper disking and harrowing, at near intervals for four or six weeks before sowing, will disturb or kill far more weeds than can any nurse crop. Besides, the oats or barley sown as a nurse will when cut leave weeds in good growth, or dormant and ready to spring up as fast or faster than the alfalfa. No nurse crop is ever used with fall sowing. When ground has been thoroughly prepared for the preceding crop, and then properly cared for, and made ready for the alfalfa by the preliminary weed destruction, it will be found advisable to sow alfalfa alone, even in the spring.