any discouragement for weevil grubs this time of year [winter]?

I hesitate to put this topic out for discussion, but with some trepidation of being considered an idiot, I do so. Here in the Municipality of Saanich we have one or two retailers selling grub control with Sevin, one with "endosulfan", and one with "permethrin". I believe the latter product is for adult weevils, not the grub. Several garden centers don't carry this sort of thing and tell me they expect Saanich to pass a new bylaw in the forthcoming year, possibly in January, outlawing all retail pesticides, as several other close by municipalities have done, except for more benign substances. I am wondering, lamely, if there is anything I can do to control weevil grubs in the soil in winter, and what the Forum community's views are [I am fairly sure what they are, but am just checking] on these chemicals. I would like to control weevils but don't want to kill earthworms and everything else. I saw in a former year's thread on rhododendron problems that one of your regular contributors had ceased planting rhodos and azaleas [perhaps he is a landscape specialist] owing to the weevil pest. I have read many of the posts on weevils and how to inspect for them at night, etc., and read of the use of nematodes as well, which I have not yet tried in the appropriate season.

 

I'm more put off by the sometimes fatal and often marring mildewing of rhododendrons here. Visibly offensive weevil damage seems to be mostly limited to those specimens planted in bad spots, like under low-branching conifers and wide building overhangs. There can also be a problem with grubs eating away the roots in nursery pots, this also seems to be associated with poor site conditions - in this case old, broken down and damp potting medium. However, I don't know if the weevils have built-up in such instances because the plant has gone too long without being re-potted (and had grubs removed along with the old medium) or if they are favored by the associated dampness.

For details on what to apply and when to apply it I would start with a web search using phrases like "weevil control".

 

Yes, that is what I have done, a web search. It seems to be chemicals, or nematodes, or nothing. Unfortunately my end of the townhouse strata or condominium estate has large groves of overhanging cedars and firs, and a north-south orientation front-to-back, so that the rhododendrons in question are a few new plantings more along the northeastern side under the overhanging trees, more or less, or certainly shaded by them, or a few hopeless ones which aren't even under discussion here which are too close to the building's deep overhang. Some dwarf rhododendrons are located more in the southerly front garden [shown here] and get a bit of sun but are shaded in summer by nearby larger shrubbery such as euonymus, hardy fuschia, and an overhead cherry tree. In the photo the latter dwarf ones are shown nestled in. None are showing extreme damage, except for the scrubby ones under the overhang not shown here. I was wondering if there are any "safe" chemical additives to prevent damage, as I have seen a few munch-marks on these dwarf rhododendrons in the photo, visible at the lower level along with some browning which fortunately has not over the year been repeated [fertilizer burn?] and was hoping to prevent damage on a few added elsewhere. I don't suppose there is anything available which would be that targeted, as the chemicals I mentioned previously would kill earthworms and other insects too.

 

sorry, somehow produced two posts here, only the above is current, and this is a mistake.