FOXGLOVE AND ITS CONTROL.

New Zealand Journal of Agriculture, Volume XVIII, Issue 1, 20 January 1919, Page 28

FOXGLOVE AND ITS CONTROL.

By

A. H. COCKAYNE,

Biologist.

Foxglove (Digitalis purpurea) is a regular garden-plant that has become widely naturalized throughout New Zealand, often in quantities sufficient to impair seriously .the. potential carrying-capacity of the ground. It is especially abundant on land that at some past time was forest, or which now represents fresh bare ground, such as riverbeds. It is not a weed of really well-grassed permanent pasture or of arable farming-land. On poorly grassed land of very low carryingcapacity it is often abundant, more especially on shady faces. -Poorly "grassed country that has reverted to bracken, badly burnt bush farms reverting to scrub, and milled forest and standing burnt forest are situations where foxglove is often prevalent. It also spreads into living forests wherever the sunlight can penetrate to the forest floor.

; In certain districts it is a gazetted noxious weed, and much money is often spent on its cutting and pulling. In many cases, however, it is difficult to get farmers to carry out such work, especially where the infested land is of a low capital = value and the areas involved extensive. Theoretically foxglove is either an annual or a biennial, but ’ in practice, owing to the development of side shoots, the plant may be "virtually . perennial. The seeds are extremely minute and produced in- countless numbers, and they often fall directly into the wool of sheep passing between the tall stems, and thus become widely distributed. Luckily the plant is rarely eaten by stock, as all portions of the plant are poisonous.

' The acknowledged methods of control consist of either pulling up or cutting down the plant before flowering. As foxglove normally is in flower well before’ Christmas,’ the work must be tackled early in the" season, and should be undertaken when the flowering-shoots are sufficiently.long to enable the plant to be easily pulled out.. If much earth adheres to the plants or if they are thrown in a moist place they will often take root again and flower. The main objection to early pulling is the fact that many plants that have not started to form flowering-stems may be overlooked, and these may probably bear seed in the autumn. On the other hand, if the" pulling is delayed until the plants are in flower much seed may be matured before the work is completed. •, . • . ■ ' '

■ ■ • Pulling is much preferred by farmers to cutting, but, personally, . I have no great confidence in the process. The pulling-up of a large foxglove-plant loosens the earth for a considerable distance and makes a ' bare space admirably adapted for -seed-germination.-. As the seed most-likely to' be in the ground is foxglove-seed, then the likelihood of further establishment of foxglove is extremely likely. I have often thought the scattering of vigorously growing-grasses, such as cocksfoot and Italian rye, and on poor land Yorkshire fog, on the ground bared

by the pulling-up of plants would be a good thing, but in many cases the expense would be too great.

Many farmers consider that it. is a waste of money to deal with foxglove at all, and under certain circumstances such a contention may be . accepted as correct.. On land that is virtually bringing no revenue, such as . fern and scrub country, pulling- cannot be regarded as a business proposition; but, of course, if the weed is a gazetted one it is a legal obligation to prevent it from flowering. If on such country it is a business proposition to pull foxglove, then how much more so is it to get rid of the fern and scrub and develop good grassland ? On country where logs are numerous a good deal . of cleaning-up of the ground, apart altogether from foxglove - pulling, should be carried out.' It cannot be too strongly.emphasized that a good sole of grass is one of the very best means of keeping foxglove out, and every effort should be made in.laying down country liable to foxglove to use high-grade seed of grasses suitable to the soil, and in liberal amounts so as to secure a rapid development of a grass-sole. On farms where the amount of work to pull or cut all foxglove is excessive it is better to do a Small piece properly than a large piece badly, and to begin with the main efforts should be directed to cleaning up the best land most likely to give the best return, leaving the other portions. The argument that the waste corners carrying foxglove are a menace to-the rest of the . land is often overemphasized, and sufficient stress is not laid on the importance of securing good thick permanent grass. . . , ■

For my part, I consider- —-and there is much evidence to back this belief-that foxglove when left untouched will in the course of years naturally disappear. No doubt the time occupied will vary on different classes of soils, but there are many areas of good second-class country where . foxglove has disappeared after being a bad weed from five to eight years. Of course, where a full return from the land is necessary to make a living the holder cannot afford to wait this period, especially as during several years when no control is undertaken large areas may be in almost complete possession of foxglove. When such a condition exists the farmer will have to pull or cut as much as possible. His work, however, should not be for the mere sake of pulling, but with the idea of getting good grassland. Hence it is folly to devote much time and money to those portions that even if devoid of foxglove would be of little immediate value. In other words, judicious selection should be made of the land over which vigorous action is to be taken.

The question of the. most effective and practical methods . of control on land where it will not pay to annually cut foxglove is one that must be answered by practical demonstration, and it may be mentioned here that a sum has been appropriated to carry out experiments in this direction. . . ,

Ensilage is specially valuable to dairymen who have to maintain a steady supply of milk all the year round for city consumption. It provides succulent feed at periods when pastures or forage crops are often deficient.