Andy's Advice on Wilding Pine Control

The satisfactory control of wilding pine depends upon several aspects:-

1:- Identify pine species and biomass to be sprayed. For example,
the waxy cuticle on contorta is more complex than the wax on radiata making it harder to kill.
Bio mass is the second thing to consider when working out the herbicide rates to used, and the amount of water to be applied so as to get complete coverage. When using non residual, non translocating contact herbicides, it is important to get complete coverage so then a good result can be achieved.
It is important to also determine whether you have to spray a two dimensional crop (small trees),or a three dimensional crop, that is, a mature crop >20m tall.

2:- Once the crop has been determined, the next thing to consider is the state of the water to be used, as alkaline hydrolysis can lock up
part, or all of your herbicide. Small quantities of a product called X-Change will chelate the cations, and drop them out of solution.                                                            Sammi McCord

3:- Before any herbicide is added it is important to acidify the water to a suitable pH so as to improve the efficacy of the herbicide. All contact herbicides work much better in low pH solutions. a product called Superquik should be added.

4:- Diquat should then be added, but not in the large quantities initially used, as the following added herbicides not only improve efficacy of the diquat, but also improve the kill in their on right. Depending upon the crop type and age, 5-15 L/Ha is recommended.

5:- Desicate, as the name suggests, is a very powerful desicate. The active ingredient is Endathol which improves the desiccation of the formulation. Rates of 5-10/Ha are recommended.

6:- The final herbicide to be added is Hammer. The active ingredient in this contact herbicide is Carfentrazone. Only small amounts are required 0.5-1 L/Ha as this product acts as a "kicker", greatly improving all other herbicides in the formulation.

7:- The final addition is Du Wett. This product is an organo-silicone spreader. Initially we used Pulse simply to get maximum spread. By reducing the surface tension of the droplets you can greatly increase the cover of applied herbicide, and therefore, reducing the amount of water per Ha, and consequently cost.

Since we are using contact herbicides stomatal wasn't required, so we looked for an alternative which unlike Pulse wouldn't breakdown in acide conditions. As in many cases we would lose up to 50/70% of the pulse before it could be applied. To counter act this loss we had to increase my rates to 5 litres/Ha.

We solved this problem by using Du Wett. This organo-silicone spreader doesn't reduce the surface tension enough to allow stomatal flooding, but does increase the spread, and doesn't breakdown as fast in acid formulation. Suggested rate 1-2 litres/Ha.

If Du Wett stainless is used, breakdown in acid solution is virtually eliminated.

Trials over time has proven that successful wilding pin management consists of either a multiple non residual spray applications or desiccate spray followed up with a burn using the "Aphid".

The idea behind a multiple spray regime is to kill the trees through starvation, simply by defoliating the trees so they can't produce starch and therefore die. For smaller trees only one application will suffice while mature 30m tall pines may need two or three.

Where we have compared aerial spraying with chainsaw work, we have always opted for the former, simply because of both the safety aspect, as well as cost. We have found that when we use chainsaws as a complete felling operation we always got regrowth primarily from coppicing especially when the crop was less than 10 years old. When chainsaws were used finish the job a few years later it proved too dangerous especially when climbing over dead slippery limbs. In nearly all cases it was cheaper, safer and less costly to finish off with an aerial application.

The only time we would recommend using a residual spray is where we are controlling seed trees, where we may only have one or two per Ha. Depending upon the age of these trees, there could be either one or many of various ages in a small area.

In these circumstances a wee R22 with a "nozzle" proved to be the most effective, as not only was the seed tree killed but also the seed in the cones as well as the seedlings around the adult tree. Of course this formulation can only be used in isolated locations as erosion would occur if broadcast application was applied. Because the immediate site has been sterilised we never have to visit that site again to control germinating seedlings.