RHAB ad nauseum
May 23, 2021 07:04PM
We imported a whole slew of RHAB from a backyard nursery about 5 years ago....one of many mistakes we have made smiling smiley)

I have spent countless hours on my hands and knees tracking the little devils to their lairs and dispatching therm with either stiff wire or a good squirt of pyrethrins.

I have come to the conclusion that I may be losing the battle..to give you an idea we had 113 trees infested at the beginning. We may be down to 70 that are "occupied" at the moment. Some of the original ones have had their tenants successfully removed and are recovering and some are new occupations.

We do the holistic sprays plus we paint all the trunks with a Kaolin slurry in early June followed by 2 applications of Neem 1% directed at the trunks through the season.

I am wondering if there is one insecticide that would be more effective against this beetle than another? Should we be using Pyganic for instance against CM and hoping that it will get some RHAB as well? We use BT, Entrust and Virosoft in rotation routinely.

Any and all suggestions welcome!

G2V Farm
Zone 5B/6
Gaspereau Valley, Nova Scotia
Re: RHAB ad nauseum
June 17, 2021 04:50PM
Chlorpyrifos aka Lorsban is the recommended chemical. It’s an organophosphate. For an infestation on your scale I would think it’s warranted.

Nat Bouman
Growing cider varieties in Zone 5b
On B.118 at 18X24
Susquehanna County, Pennsylvania
Re: RHAB ad nauseum
June 17, 2021 08:20PM
I'll admit going the chemical route was a temptation some twenty-five years ago when my journey with borer began in earnest. Simply put, you can't grow apples without trees! I even mentioned Lorsban in the first edition of Apple Grower as a fail-safe consideration when constant vigilance becomes too much. Back in the 90s, organic fruit growers were coating young trunks with diluted latex, joint compound, diatomaceous earth, and whatever else might possibly repel the female beetle that oviposits the "grub from hell" in young apple trees. Much angst went into finding a sane solution... and as updated last summer in Borer Repellent... the answer can be found by directly applying pure neem oil to trunks. I'm going around now scything/ mulching younger trees and it is such a blessing to see that not a single tree shows sign of RHAB so far. Read that thread and take hope, Joanne.

Meanwhile, let's be mighty clear about the Lorsban option: Chlorpyrifos is one of those chemicals that should absolutely be banned from the face of the earth. Just in case any ambiguity lingers from those earlier writings of mine. cool smiley

Lost Nation Orchard
Zone 4b in New Hampshire

Edited 1 time(s). Last edit at 06/18/2021 04:25PM by Michael Phillips.
Sorry, only registered users may post in this forum.

Click here to login