PG Suspension – Applying in the field

A biological control agent for Heterobasidion annosum (formerly known as Fomes annosus)

• Keep the sachets cool during transport to the site. (You could keep them in a vaccuum flask of cold water).
• Dilute the contents of each sachet in a small amount of clean water, mix thoroughly, and then make up to 25 litre.
• Apply this suspension to stump surfaces immediately after cutting at a rate of roughly 1 litre per square metre – i.e. just to the point of run-off – ensuring that the whole surface is covered.
• Application can be:
  • Manual – using a 5 litre polythene bottle fitted with a brush top.
  • Mechanised – through the harvester using nozzles situated close to the cutting bar, or through specially designed bars with holes drilled along the length.
• The minimum and maximum rates of application are 7 to 100ml of product per hectare. (This will vary between operations such as thinning small, unthrifty stands or clear-felling mature crops.)
• Only make up as much PG Suspension as you need because any excess working solution must be discarded at the end of each day by pouring onto stumps. Fresh solutions have to be made up at the start of every working day to ensure viability.

Note

If you intend to use equipment which has previously been used to apply urea, make sure all the tanks and hoses are thoroughly rinsed with clean water before using PG Suspension because the urea might impair the viability of this biological product.

Related pages

• Conifer root and butt rot (Heterobasidion annosum) resources page