Looking At Tougher Sheets

Press, Volume CVI, Issue 31107, 9 July 1966, Page 10

Looking At Tougher Sheets

“VVE are working on tougher v plastic materials,” said Mr G. Jowsey, technical adviser to Blades Chemicals, referring during a convention for South Island dealers handling vacuum silage equipment in Christchurch this week to the sheets used for stacks.

In the United States, he said, what was known as “double tuff” was 90 to 100 per cent stronger than standard polythene, but before this or other materials could be used a lot of work had to be done. They had first to be satisfied with the job that they could do, and also the selling price.

In England it had been found that stalks would go through butyl rubber as easily as through polythene. This was a heavy material that certainly stuck to the stack and with a big stack it would be necessary to use a front-end loader to put on the top sheet. A possibility would be a material that would be somewhere between

butyl rubber and "double tuff.”

But meantime, Mr Jowsey said, farmers in the North Island who were going into their fourth season with vacuum silage were quite happy with polythene for a cover. It was 100 per cent adequate for the job, but they would get something tougher. In the course of his remarks Mr Jowsey said that perfection could be reached in the making of vacuum silage if farmers adhered strictly to instructions.

He said that it was most important for sheets to be tied down. If the stack was not airtight there would be wastage.

To help in sealing some farmers, he said, had used grass around the base of the stack and put concrete posts on top of that Mr Jowsey said time of cutting material for vacuum salige was important. It should be at the 10 per cent ear emergence stage. It was also desirable for farmers to plan ahead the paddocks they

were going to cut for silage and use a little 2,4—D to control weeds in these swards. Much less pressure was now needed on a stack than had been thought by a lot of people, he said. It was necessary to talk about vacuum pressure at the stack, he said. He proposed the use of a milking machine gauge at the stack.

To save oil from the pump unit splattering over the sheet and causing brittleness, Mr Jowsey suggested that a sack might be wrapped around a short extension pipe out from the pump to trap the oil while letting the air go through. Mr Jowsey said that molasses as an additive to silage increased the palatability and resulted in a bigger return than the expense. Where in

America a chemical was added to material in ’tower silos it had been found that the intake of cattle had been increased by 10 per cent and weight gain by 15 per cent.