Results so far on the partial-breaking and breaking-down of tree/shrub weeds

In answer to a query "how's this technique working out so far?":

Firstly, the trial is based on intuition and previous casual experience; ie this technique has been found elsewhere to be a practical solution on small juveniles in shade, when its not easy, or is undesirable, to uproot them - eg on a bank prone to erosion, or where their complete removal would disturb the roots of other plants.

In our casual experience to date on other sites, after a year or so of yearly treatment, small juveniles in shade have been found to have weakened enough to be pulled out with little effort or soil disturbance.

Elaeagnus, abundant along the path through Eskdale Forest in dry ground, still aren't easily pulled out a year or two after this treatment. But they don't grow significantly, so it is a practical solution for bush-walkers who can identify them; it only takes a few seconds to stop them taking over the next bit of understory in the next year (and becoming too thorny to handle).

Here are all observations of Ligustrum spp, ie Tree and Chinese privets, in the Gahnia Grove site, in order observed, including all re-observations after interventions.

Luxuriating in full morning and partial afternoon sun, the 3-4m Tree privet in Gahnia Grove, in June 2018 and in Aug 2018, showing numerous buds and branchlet regrowth after 3-4 months. However, it can be "broken down" again in a matter of seconds, as all branches are within reach. It's then easy to knock off the buds and break back any new branches.

The longest were found in October, about 30cm long but still soft enough to be broken back easily.

So far, on the big ones like this at Gahnia Grove, in a dense native planting in which these tree privets had overtopped and were suppressing the adjacent native trees, it takes less than a minute to prevent them being an immediate threat to the expansion of its native neighbours. This has been done approx monthly since July so at this stage can't be recommend ed for eg an annual programme. (though it may well result in less regrowth than felling).

It remains to be seen what the longer-term results will be with the monthly one-minute de-budding and knocking-back.

Also being trialled at Gahnia Grove is ringbarking combined with lower-branch removal, on one about 3.5mH that was too tall and rigid to be pulled down. Leaving the top growth on helps starve the tree, we suspected and have had confirmed by others.

The tallest one here, its lowest branches partially broken and bent down, and its trunk ringbarked, in Mar 2019 shows no new growth in the top part, but has put out new shoots just below the ring-barking. At least these are easy to reach! But they will impact on adjacent trees if not controlled.

Posted on October 8, 2018 05:41 AM by kaipatiki_naturewatch