I just remembered spraying a Boric Acid solution on the frame of our house we build about 8 years ago and looked to see what all Boric Acid would kill....attaching the article....looks like boric acid is going to get my vote...
"Boric Acid
If a product can kill a cockroach it is probably not good for humans either. Many pesticides are extremely harmful to the human nervous system, so safer, non-toxic remedies are a wise choice.
Boric Acid, a white powder, is mined from the Mojave Desert in California and is nature's proven long-term treatment in eliminating Cockroaches, Palmetto bugs, Waterbugs, Ants, Silverfish, Carpenter Ants, and Termites.
This chemical has many interesting and useful characteristics. A few are discussed here such as use as an insecticide, a preservative,and a fire retardant.
The first use of borates as an insecticide was in 1922 when P.F. Harris invented the Roach Tablet. It evolved into many products including today’s “Roach Motel”.
By 1985 there were over 200 registered pesticides containing borates.
In 1955 framing lumber in New Foundland began being treated with borates to control an epidemic of termite destruction. Since then, none of the homes using borate treated wood has had any infestation of termites or wood decay.
In the 1970’s Europe and the US began studying borates for wood preserving properties. There was a huge lawsuit involving an US lumber company that put tropical hardwoods in over 1000 homes. The hardwood had beetles in the wood. The homes were treated with borates and the hardwood mills in South America began pre-treating their wood with borates. Since then there have been NO problems with beetles.
This simple inexpensive, household chemical is deadly to all insects. It has been shown to attack their nervous systems, as well as being a drying agent to their bodies. In combination with certain chemical solvents ( such as propylene glycol ) it may migrate slightly into such objects as wood and concrete, following the solvent, and providing some degree of lasting protection. Commercial development of such products are Bora-Care, and Boric Acid type insecticides & products. (See Wood Rot)
As a general household insecticide Boric Acid is safe enough to use around children, and has been used in ointments and salves for diaper rash on babies. It is also used, in a very dilute solution, as an eyewash. How Safe is it? (New Window opens)
Another well known and thoroughly proven use is in fire retardancy. It is the fire retardant used in all blown type cellulose insulation commonly used in homes.
Natures Insecticide:
Boric Acid is the "secret ingredient" in so many commercial treatments for insect control. Boric acid (100%) powder is odorless and nonstaining. Kills roaches,termites, fireants, palmetto bugs,ticks,bedbugs, fleas, boxelder bugs, carpet beetles, centipedes, crickets, earwigs, grasshoppers,millipedes, scorpions, slugs water bugs,and many many more creepy crawly insects.
Ants : This past year have been on a rampage here in Fl, the insect capitol of the world. This homemade treatment has worked very well on both carpenter ants and pharaoh ants.
Ingredients:
1 Tablespoon of Boric Acid, 1 tsp of Sugar, 4 oz water, Cotton Balls.
Mix Boric Acid and Sugar in a bowl. This can be poured over a cotton wad in a small dish or bottle cap. Keep this from drying out for continued effectiveness. Place Cotton balls in path of Ants.
Roaches: Boric acid powder, is often called "roach powder". Here is a great remedy from Heloise "Boric Acid Roach Exterminating Formula"
Rid your home of silverfish, those hungry, nasty-looking insects that live under your sink, your drawers, or closets and feast on valuable clothing and important papers.
Termites:
Boric acid when mixed with propylene glycol (non-toxic version of anti-freeze) has proven to be very effective against many types of termites. The glycol helps the solution to penetrate into the wood and become a part of the wood fibre. This solution is a terrific treatment for dry rot in wood.
Kill Silverfish Quickly:
Mix a small amount of boric acid, 20% or so with an inert ingredient like "whiting" fold into small packets and place them in dresser drawers, under your sink, or closets to kill silverfish quickly with absolutely no mess.
A Safe Surface Insecticide may be formulated by dissolving Boric Acid in plain water to make a 5% to 10% solution of clear liquid. Heating the water first makes it easier to dissolve the white powder. This simple inexpensive, household chemical is deadly to all insects, is safe enough to use around children, and on interior surfaces (test first on a small hidden area to check for possible -- but rare -- discoloration of finishes). Don't expect instant results, give it some time, occasionally additional applications are needed. It lasts about a year, or until the surfaces are washed. Many modern applications of this ancient item are showing up in products, and commercial treatments.
To apply as a powder, you can use and old grated cheese shaker [make sure it has lots of holes] or an inexpensive mustard or condiment squeeze bottle. Some important places to make sure you treat:
around all pipe and drain entrances in floors and walls
in and under all cabinets, especially corners and cracks
around all baseboards, in corners and on top of cabinets
behind and under range, dishwasher, and refrigerator
In new homes, during construction, the powder can be sprayed inside walls, soffits, and in the attic. Also, it is a good idea to apply the powder along the top of basement walls near the ribbon-plate [where floor joists rest on the conrete wall of the basement].
For carpenter ants drill holes in wood surrounding infestation, fill with boric acid
Fleas:
Simply sprinkle it on the carpet, ( same mix as above for silverfish) brush it in so it settles down and in the fiber, let it sit for about a week then vacuum and fleas will be gone, eggs and all!
An EPA assessment of a boric acid pilot pest control program conducted at the U.S. Army’s Aberdeen Proving Ground in Maryland found that boric acid was both more economical and more effective than a monthly spray treatment. Do to its unique mode of action, insects do not gain resistance to borates. It is water resistant, heat resistant and remains effective for long periods of time. Borates are the most effective treatment for many crawling insects including, cockroaches, silverfish, larder beetles, carpenter ants, and other wood borers, as well as wood decay organisms .
