PGG Wrightson Central Otago wool representative Graeme Bell said for the experiment he helped bury two jerseys in the grounds of St John’s School in Ranfurly about five years ago.
One of them was a school jersey made mostly of synthetic material. The other was a woollen windbreaker with a plastic lining and zip.
Mr Bell and the pupils dug up the remains of both jerseys last week.
The only degradation of the synthetic jumper was a missing cotton badge of the school logo.
"You could have washed the jersey and wore it again."
All that remained of the woollen windbreaker was the plastic lining and zip.
"The pupils were absolutely astounded by it all."
They were amazed by how the wool had broken down and become fertiliser, which then helped the grass grow, which had the potential to be eaten by a sheep to grow more wool.
Since the original project was launched, the school jersey was now made of wool.
On the same day the jerseys were unearthed, a new experiment was launched involving burying a woollen school jumper, a piece of synthetic carpet and some plastic bottles.
Pupils would dig up the items in several years.
The experiments were part of The Campaign For Wool programme.
As part of the programme, a Wool in Schools shipping container was converted to a classroom and placed at the school to help primary school pupils understand the benefits of wool.
Mr Bell said he had been involved in the wool industry since 1968 including as a handler, classer and shearer and had always believed in wool as a product.
"I’ve had a passion for the fibre all my working life."
