PRESENCE OF NASSELLA IN SEED FALLS OFF

Press, Volume CXI, Issue 32802, 30 December 1971, Page 9

PRESENCE OF NASSELLA IN SEED FALLS OFF

Procedures under the Nassella Tussock (Grass Seed) Regulations, 1958, are being modified from the beginning of January.

The fields superintendent of the Department of Agriculture in Christchurch, Mr A. R. Dingwall, says that these changes are designed to simplify procedures and significantly reduce the considerable time and eSort involved on the part of seed dressing operators and testing and administrative staff, while at the same time retaining adequate safeguards against the distribution of nassella tussock seed impurities in commercial lines of grass, clover and lucerne seed. “The regulations were first introduced in 1949 following evidence of nassella impurities in a number of lines of seed produced in certain districts in North Canterbury and the possibility of similar occurrences in certain Marlborough seed producing areas,” said Mr Dingwall. “They were subsequently modified in 1958, to tighten up on certain aspects, particularly those relating to the sale and sowing of infested-seed lines. “During the early years of their operation, the regulations were responsible for preventing the widespread distribution of nassella impurities in many seed lines. “For example, in the four years 1954 to 1957, some 102 lines of commercial seed were found to contain nassella. The sale of these lines was prohibited until such time as all such impurities had been removed, and the contaminated offals destroyed. “In contrast, only six instances of nassella were detected during the six seasons, 1965 to 1970, and two of these were in old seeds that had been in store for six to 10 years. “The last instances of impurities in current season’s harvest occurred in 1965, when four lines, totalling only four sacks of white clover seed dressings, were found to contain nassella. “During the five-year perlod, 1966 to 1970, no

nassella impurities have been detected during the year of harvest, in the 4760 lines tested nor in any other lines apart from two old stock lines mentioned one of which comprised a blend of 21 part lines of white clover, and the other, three sacks of old lucerne seed dressings. “Nor have seed certification officers detected nassella tussock at field inspections, in any certified seed crops during the past 10 years. “The regulations have nevertheless, served a very useful purpose in intercepting many. hundreds of nassella contaminated lines during the past 22 years. “However, records and evidence -of the past six years indicate that there is now only the remotest chance of these undesirable impurities occurring in commercial seed lines, and then only in lines of very old stocks of white clover or lucerne seeds that might still be held in farm sheds or seed stores. “One of the main reasons for the marked decline over the years in the occurence of nassella impurities in field-dressed seed lines has been the operations of the North Canterbury Nassella Tussock Board in successfully suppressing all extensive, densely-infested nucleus areas within its district. These areas were the source of much of the nassella which, both directly and indirectly, contaminated seed-producing crops in-the. past.

“Under the new. modified regulations, which come into operation from January 1, the withholding and testing of seed for nassella impurities before approval to sell is granted will be confined only to white clover and lucerne seed produced on certain properties within the prescribed area of North Canterbury. “A schedule list of property owners on whose farms seed may be produced and which might contain nassella impurities has been compiled. “Seed dressing operators throughout North Canterbury from the Rakaia to the Conway Rivers have been provided with a copy of this schedule and will be required to apply for and have tested any lines of white clover or lucerne seed originating from any property included in the schedule. “These conditions will apply to all such lines of clover or lucerne, irrespective of whether they are harvested as field-dressed lines of clover or lucerne, or result from dressings out of grass seed lines. “Seed dressing operators’ applications for permits may now be submitted direct to their nearest local office of the Department of Agriculture. These applications will no longer require to be submitted for consideration to the department’s Rangiora office, as in the past. “However, seed growers in the prescribed area of North Canterbury—which extends from the Ashley River northwards to include the formei- Kowai county and the existing counties of Waipara, Amuri and' Cheviot—are especially reminded that Section 6 of the Nassella Tussock (Grass

Seed) Regulations, 1958, still applies. “This section decrees that any grass, clover or lucerne seeds grown in the prescribed area, must not be removed from the area except on consignment to a stationary seed dressing plant located between the Rakaia and Conway rivers. Also that such seed must not be otherwise removed until its has been machinedressed and, where appropriate, until such time as the results of a nassella search and clearance have been obtained. “Copies of the property owners’ schedule are held ' at local offices of the department in North Canterbury,” said Mr Dingwall.