Drywood Termites are a mutation from the main type of termites – Subterranean Termites which are important part of overall ecosystem in nature. As opposed to Subterranean Termites which live deep in the soil in form of colonies, drywood termites live inside the wood or anything containing cellulose without a need to be surrounded by soil for access to moisture and easier ways of communication with other colony members.
This is possible only if drywood termites do not die naturally due to less stable temperature and moisture content. As any living organism, drywood termites need water which they extract from the wood they live in and eat. They also need certain levels of temperature which will insure their low mortality rate and survival. If the moisture content in the air is not sufficient, then it drastically decreases the population of drywood termites close to complete absence of them. On the other hand, if the moisture content is comparatively high which is the case with coastal areas, then it results in much less mortality rate among drywood termites and higher possibility or even guaranteed presence of them.
The temperature is important for drywood termites as well. There are two factors regarding the temperature – variance of temperature and average temperature. For drywood termites do not get naturally frozen or being exterminated due to extra heat, areas with comparatively stable temperature are needed. At the same time temperature needs to be warm enough in general.
The below drywood termite incidence map shows this in quite an illustrative way.
The photo below shows drywood termite incidence map for the continental USA. Please, note that states of Hawaii and Alaska are not included. While State of Hawaii has a high drywood termite infestation level, there is no drywood termites in State of Alaska.
Drywood Termite Incidence Map in the continental USA
It clearly shows that drywood termites are more widespread in Southern coastal areas having higher temperature due to being in lower latitudes. At the same time West Coast has higher incidence of drywood termites in general due to stronger influence of Pacific Ocean compared to that of Atlantic Ocean.
Thus, Southern California, Southern Florida, and Hawaii are the areas where drywood termite infestation is the highest in the USA. And again, the closer to the ocean line we go the higher gets drywood termite infestation intensity within these macro-areas.
According to our vast experience of doing inspections in thousands and thousands of homes in Southern California and more specifically in Greater Los Angeles Area we show Drywood Termite Infestation Intensity Map in our Service Area below.
Drywood Termite Infestation Intensity Map in Southern California – Greater Los Angeles Area
There are three main factors to consider here.
First, the closer to the Ocean – the more severe becomes drywood termite infestation. This is due to existence of more stable temperature and moisture content. Pacific Ocean serves as a stabilizer of temperature since absorbs the energy of the Sun and dispenses it more stably. This applies in greater extent to areas closer to the ocean. The more inland we go the more continental gets the climate and the moisture content gets less since the areas become farther from the pool of huge amount of water – Pacific Ocean. This results in less intensity of drywood termites. In this case we are talking about intensity of drywood termite infestation as opposed to incidence of drywood termites in the USA. This is because overall Southern California has a high incidence of drywood termites since almost every structure gets infested by drywood termites unlike say Sacramento where only some percentage of structures show this type of infestation. There have been even cases when drywood termites were found in Toronto, Ontario, Canada. However, it was quite a rare phenomenon in that city. This means Toronto has very low incidence of drywood termites, though intensity of that very infestation might have been high. This might be the case If say, the lumber which that building was built by was brought from Florida with already infested drywood termites inside.
Second factor is the year house or other structure is built. If there is an add-on on the structure then the year the add-on is built. The wood in newer houses is much more conducive for drywood termite infestation for two reasons. First of all, houses built after 1970 have a very soft wood since the trees from where lumber is produced are younger. After 1970 there were few cases when lumber producing companies would cut the trees which were 100, 200 or more years old. The trees from which lumber is produced usually are 5-15 years old. This results in much softer wood which itself is much easier to eat for drywood termites. In addition to this, the more the lumber stays the more moisture it losses by time. By other words older wood gets drier by time since it naturally loses some part of its moisture after being cut for lumber production. This results in less moisture content and less chances of drywood termites flourishing in structure.
This is why all houses and other structures in Southern California and specifically Greater Los Angeles area need constant inspections, maintenance and treatments for drywood termites.
The third most important factor is when was last drywood termite work done and what type of work. At the present as of the end of 2009 there are two types of complete drywood termite treatments.
1. Fumigation with Vikane, Zythor or Master Fume gas done with good quality which insured 100% or close to 100% elimination of drywood termites. If you were trying to shop for the best price since were thinking all fumigations are the same, this might not be the case. I would suggest additional inspection after fumigation.
2. Complete Heat or Thermigation treatment not on certain areas on the structure but on entire structure where the tent was put on the house and tenants or owners moved for a day or so to allow the termite company to do complete Thermigation.
Please, note that Orange Oil or XT-2000 is not a complete drywood termite treatment for obvious reasons. At the same time termite control includes termite extermination and termite prevention. In case of drywood termite termite prevention is most of the time a better type of control than termite extermination.
There are less important factors as well such as quality of limited treatments including Orange Oil, Foaming and other limited treatments which could not guarantee complete extermination of drywood termites. We take this into consideration when qualifying houses for free complete inspection since in these cases many times visible and accessible infestations are treated. However our matrix does not take this into consideration for predicting termite infestation level since again, even if half of drywood termite colonies were left without extermination, it still does not change the fact that house has a certain degree of infestation level. Another very important factor is the proximity of house or other structure to neighboring structures. There are very few, less than 1% of houses which are more than 50 feet further from houses of neighbors. These houses are in high-income areas, on the hills but again extremely rare. Since drywood termites infest from one home to another, if the closest house is more than 50 feet further from any other house, it makes difficult for drywood termites to infest. However, we have not incorporated this into our matrix because again it is extremely rare. Another important factor is if complete drywood termite treatment was done and at the same time or within a year drywood termite preventative measures were done such as preventative painting, Timbor Professional or Boracare spray in accessible wood members. For instance if house was fumigated and at the same time inorganic or other types of wood preservatives were introduced, especially if they were also injected to inaccessible areas by liquid foaming or misting, then these houses will not have problems for very long time – 20, 30, 50 years or more, provided that these treatment were done professionally. While Prime Termite uses this method in many cases, especially for new houses in coastal area, however from our practice we do not see significant amount of houses where complete drywood termite treatments and in addition to it good preventative treatments and/or other measures were done. This is why this factor is not being included in our matrix.
Now we will show what will be drywood termite infestation in certain areas.
The Termite Matrix incorporates these principles and allows users to know with a great deal of accuracy the state of drywood termite infestation in their homes or other properties.
Please, note that houses and other structures located more than 2500 feet above sea level, being 100 feet or further from any neighboring structure as well as those built before 1920 regardless of area are excluded.
Area 1 – Ocean line – PCH (Click photo below to see larger image)
This area of drywood termite infestation includes Southern Part of Malibu, coastal part of Santa Monica, Marina Del Rey, El Segundo, Manhattan Beach, Hermosa Beach, Western Redondo Beach, Palos Verdes Estates, Rancho Palos Verdes, Rolling Hills, coastal Part of Long Beach, Seal Beach, coastal part of Huntington Beach, coastal part of Newport Beach, coastal part of Laguna Beach. If name of city is not in list you may put your address on google maps and locate the property area.
Houses South (Below) or West (Left) from Pacific Coast Highway (PCH)(refer to photo above) built prior to 1970 most likely have drywood termite infestation which requires serious inspections and treatments unless they received complete drywood termite treatments in last 7 years. Local treatments do not count since they mainly mask the infestation and let the damage continue in other areas.
Houses West from Pacific Coast Highway (PCH) built after 1970 most likely have drywood termite infestation which needs to be controlled if they did not do any fumigation or complete heat in last 5 years.
Area 2 – PCH-101/PCH I 405 (Click photo below to see larger image)
This area of drywood termite infestation includes Northern Malibu, Eastern Santa Monica, Inglewood, Lennox, Hawthorne, Lawndale, Torrance, West Carson, Long Beach South from I405, Signal Hill, Eastern part of Seal Beach, Eastern Huntington Beach, Costa Mesa, Irvine west from I405, Lake Forest, Laguna Hills. If name of city is not in list you may put your address on google maps and locate the property
For houses between PCH and 101 or PCH and I 405 built before 1970the above concerns if no complete drywood termite treatment was done within last 10 years.
For houses in the same area built after 1970 it is for last 7 years.
Area 3 – 101-118 or I 405 – I 5 (Click photo below to see larger image)
This area of drywood termite infestation includes West Hills, Woodland Hills, Chatsworth, Canoga Park, Reseda, Winnetka, Northridge, Tarzana, Granada Hills, Sherman Oaks, Panorama City, Studio City, Sun Valley, North Hollywood, Hollywood, Bell Air, Beverly Hills, West Hollywood, Burbank west from I5, Glendale west from I5, Huntington Park, Florence, Norwalk, Bellflower, Lakewood, Cypress, Garden Grove, Stanton, Santa Ana, Irvine east from I405. If name of city is not in list you may put your address on google maps and locate the property area.
For houses located North (Up) of 101 AND at the same time South (Below) of 118 or East (Right) from 405 AND at the same time West (Left) from I 5 there should be drywood termite problems if no complete work was done in last 12 years.
For houses in this area built after 1970 the above concerns if no complete drywood termite treatment was done within last 10 years.
Please, note that the more South we go towards to Orange County line when I405 gets closer to I5 the more chances of drywood termite infestation and need for complete or partial control exist. In order not to complicate our system too much we did not take this into consideration, however if house is South from 22 freeway you can deduct 2 years from these numbers. Our company does not service area South from the point where I 405 merges with I 5, however these areas become similar to our Area 1 West from I 5 or Area 2 East from I 5.
Area 4 – East from I5 (Click photo below to see larger image)
This area of drywood termite infestation includes City of San Fernando, Burbank east from I5, Glendale east from I5, La Canada Flintridge, Pasadena, South Pasadena, San Marino, Altadena, Arcadia, Monrovia, San Gabriel, East Los Angeles, Montebello, Pico Rivera, El Monte, Hacienda Heights, Covina, Whittier, Rowland Heights, La Habra, La Mirada, Fullerton, La Mirada, Anaheim Orange, Placentia, Tustin, Yorba Linda, Pomona, Chino, Chino Hills, Claremont, La Verne, Ontario, Upland, Rancho Cucamonga, Corona, Fontana, Riverside, San Bernardino. If name of city is not in list you may put your address on google maps and locate the property area.
Houses located East (Right) from I 5 need drywood termite complete or partial control if no complete drywood termite work was done in last 12-15 years for houses built before 1970. Houses in this area built after 1970 will most likely require complete drywood termite control instead of complete or partial control if no complete work was done in last 12-15 years.
If we go East from Glendora, San Dimas, Claremont, Pomona, Corona and East from I15 before it reaches 91 freeway, homeowners should be concerned about drywood termite infestation in case no complete work was done in last 15 years. This includes San Bernardino and Riverside.
If instead of fumigation and complete heat other treatments were done the following need to be taken into the consideration.
1. If localized treatments were done when only spots found were treated, it did not do much for controlling the drywood termite infestation except masking infestations and not letting termite inspectors know the state of the house. For example, if there are 3 termite infested spots in the house in accessible wood members which comprise only 10% of the overall wood members in the house, then there will be 9 or 10 times more drywood termite infestations in the rest of wood members which are not accessible to inspect. As shown above, drywood termites prefer more stable temperature and moisture content, and interior wood members covered by exterior and interior walls have more stable moisture and temperature.
2. If limited treatments were done such as Boracare foaming and Orange Oil or combination of electrocution, freezing, liquid nitrogen and other treatments, then unless the company worked at home at least 2-3 days uninterrupted these treatments should be downgraded as localized treatments. If company worked there at least 2-3 days. then inspection is recommended to know the details. We have seen many cases when even extensive limited drywood termite treatments did not solve the problem, and houses continued experiencing drywood termite structural damage and incurring costly repairs. Since in these types of treatments most infestations are masked we do not offer free complete inspections unless customer already noticed problems themselves.
Below are some photos showing drywood termite structural damage done during our inspections.
On the photo above, structural damage is done by drywood termites on main beam in subarea which requires replacement.
On the photo below drywood termite droppings similar to sawdust are noted in small open area on stucco while the rest of infestation cannot be seen due to being in inaccessible areas.
Other type of Drywood Termites – Dampwood Termites are much more dangerous and cause faster damage, however they are not common in Southern California.