Root Phosphonate Testing
Sampling procedure for root phosphonate test:
- Avocado roots are soft and easily damaged.
- They will also decay very quickly if left to sweat in a bag.
- Phosphonate ion is easily leached and very water soluble.
- Be sure to detail method, timing and frequency of treatment
This is a first draft and subject to change as we learn/validate from field data
1. Timing: Preferably 2 weeks after treatment, but this is not essential. Sample during a root flush (spring or autumn) so that the majority of the sample is new white feeder roots from the mulch layer (pencil down to fine).
2. Representative sample: Take from a range of trees within a block and range of position around the tree. But keep tree age, health and history consistent.
3. Avoid delay: Sample on a Monday morning and courier immediately to Hills.Do not sample mid to late in the week.
4. Damage/Decay/Dessication: Root sample must arrive fresh and undamaged. Avoid drying out, sweating in a plastic bag in the sun, crushing. Use as long sections of root as possible. Wrap root sample in kitchen towel/tissue and send in a paper envelope or ziplock bag.
5. Quantity: 10g to 50g as demonstrated
6. Leaching: Do not wash roots as phosphonate is extremely water-soluble.
Prepared by Jerome Hardy, Primor Produce Limited