Water Weeds

Press, Volume XCVII, Issue 28701, 26 September 1958, Page 9 (Supplement)

Water Weeds

Broad-leaved weeds such as water-cress and buttercups and grass species such a floating sweetgrass, tall fescue and cocksfoot are among the weeds which interfere with the flow of water in drains and water-races.

Experimental work on this problem is being carried out and materials which have been or are being tested include the total weedkiller, monuvon, dalapon for grassy weeds and 24D ester for v broad-leaved weeds. Weeds which commonly occur in riverbeds, roadsides, railway reserves, about stockyards and in other similar situations are included here.

Gorse and broom abound in the broad Canterbury riverbeds. Broom is not a very aggressive weed, while the gorse seed weevil has probably had some effect on

limiting the spread of gorse. Both can be killed with 245 T hormone spray.

It may not be generally known that nassella tussock is established in the beds of at least two major rivers outside the nassella .board's area. Efforts are being made to eradicate the infestations but already a good deal of seed must be present in these localities. Exposure of the ground surface such as occurs when gorse is burned, allows nassella seedlings to spring up in great numbers. Unless this land can be induced to grow pasture of sufficient vigour to suppress' nassella tussock or is regularly cultivated to prevent further production of nassella seed, it is better to remain in gorse.

In Canterbury, gorse is preferable to nassella tussock.