Q: I have a buffer zone in my farm and rose of Sharon are coming up around the trunks of my oak trees. Will this harm the oaks? – M.S., Albuquerque
A: The only concern I have, and was able to research, was if there would be a competition between the oaks and the rose of Sharon.
From the photos you forwarded with your question, the shrubs look like rose of Sharon – Hibiscus syriacus – which are very sturdy plants grown easily in these parts. If they are the rose of Sharon plant, then you’ll have lots of flowers later in the year to offer pollinators an even more varied diet. Also, the blooms are so very pretty.
The “competition” might come from the want of water. It might be best that you cut away the rose of Sharon from the base of the oaks to keep the trunks as healthy as you can. I would not recommend applying any sort of herbicide on the rose of Sharon, since it could too easily affect the oaks.
Also, from all I’ve read about tending oak, it’s recommended that you create a moat surrounding them, so the oaks don’t have water lapping directly on their trunks.
The oaks, from the pictures, look good and having the rose of Sharon – if they are rose of Sharon plants – cohabitating shouldn’t be a big issue. But the ones that are growing from the same spot as the oaks could be cut back, giving the oak more air.
I could find no caution suggesting that a rose of Sharon will poison the oak, but I suggest you speak to an oak lover. Trees That Please, a nursery in Los Lunas, grows a lot of oaks and they might be able to shed far more light on your concerns about the interloping rose of Sharon you have living so close to the oaks.
Me, I don’t see a huge concern, other than the competition for water, but hope you will continue to seek out more information to keep the oaks healthy.
Good luck.
Q: Have you got any more ideas on the prevention of mosquitoes? I really don’t want to be pestered by them like last year while trying to enjoy the patio. – S.A., Albuquerque
A: Well, I’ve done a bit more research and did receive some mail on the subject of mosquitoes.
The most effective way to eliminate mosquitoes is to prevent them. First and foremost, eliminate spots of standing water where they could lay the eggs. You might be amazed with just how little standing water can become a home for mosquito larvae, in turn growing to become those nasty, sometimes disease-ridden creatures. Adult mosquitoes are the scourge of any outdoor gathering.
Get out there in the landscaping and find any collection of pots, tires laying on their sides, abandoned pails left in the sand play box, a glass of water from a previous celebration, and the saucers under your patio pots. These spots will easily become mosquito nurseries.
One reader led me to biological control in the war on mosquitoes. There are available products that contain Bacillus thuringiensis species israelensis; Bti for short. Now this should not be confused with another Bacillus thuringiensis, Btk, that is touted as a caterpillar insecticide. You need to be specific. I found it, the Bti, available as “mosquito dunks” at two pond supply retailers here in the Metro. The dunks look like doughnuts and are meant to be floated in pond spaces with standing water.
The good thing about this biological control is it is very specific about what insects it controls. Listed as the insects it attacks are black fly larva, fungus gnat larvae and the mosquito larva. It is safe for use around humans, fish and most every beneficial insect around. I’ve learned that it shows no harmful effects on honeybees, either.
Being a biological control, one that shows up naturally in the soil, it’s a good weapon to employ in your fight with the mosquitoes. I have several patio pots that are notorious for holding water and am thinking of getting the Bti, crunching it up a bit and placing a small amount in the saucers. That way, any mosquitoes that hatch living in that standing water won’t grow to adulthood.
If you have a pond or water feature in your landscaping, consider adding some mosquito fish to the pond. These voracious creatures love eating mosquito larva. They look like a plain brown guppy and won’t detract from any showy fish like koi you might be tending.
But really, the best way to control mosquitoes will be the elimination of any spots that collect standing water, period. Get out there and see what you can find, you just might be surprised by what you do find.
Happy Diggin’ In!
Tracey Fitzgibbon is a certified nurseryman. Send garden-related questions to Digging In, Albuquerque Journal, 7777 Jefferson NE, Albuquerque, NM 87109, or to features@abqjournal.com.