Garden scene with the words Landscaping and rat harboragePet rats – the kind you buy at the pet store – can make the most adorable friends. Our daughter had one as a pet and she was a very beloved family member.

But rats in the roof, attic, crawl space, walls and landscaping are not so adorable. They wreck havoc and can cause damage to home and health. Wild rats gnaw on wood and wires, and they carry fleas that can spread disease. Further, their droppings can be unhealthful, too. There are many reasons to make sure that rats aren’t at home in your home, garage, or yard.

What kind of rats exist here?

In Silicon Valley, the predominant type of wild rat is the Roof rat (also known as the Black Rat, Shop Rat, or Tree Rat).  They are identifiable because their tail is longer than the head and body together. They are dark brown or black in color. They do not live only on roofs or in attics, but do appear to prefer higher places, like branches in trees.

A lesser seen rat in the San Jose area is the Norway rat (also called the Wharf Rat, the Sewer Rat, or the Brown Rat). This rat has a shorter tai; and larger, heftier body with light brown or gray coloring, and may be seen in more rural or less developed areas.

A few years ago, a neighbor of ours found a dead rat in his yard, and he called The Santa Clara County Vector Control District office to come out and help him identify if there was a problem with rats getting into his home or not, and to shed light on the issue of why this critter recently appeared in his home. The officer came out and performed this service for free, enlightening my neighbor as to access points and providing a helpful brochure about rats and what attracts them.

Landscaping and rat harborage

I’d heard that Italian Cypress trees, juniper and ivy were all bad – that is, that they attracted rats and create a nice setting for them, or rat harborage. What I did not realize is how many other things do too.

Here’s a partial list of landscaping to avoid if you want to not attract rats:

  • Italian Cypress Trees
  • Juniper Tams
  • Algerian Ivy
  • Date Palm Trees
  • Bamboo
  • Honeysuckle
  • Star Jasmine
  • tall weeds or grasses

Other rules of thumb to avoid enticing rats to your yard:

  • no climbers
  • low growing – not more than 10″ high
  • plants providing fruit should not be used
  • clutter that can provide a nice shelter or conceal their presence (stacks of newspapers, firewood, etc.)

I dislike ivy and juniper (and grew up with a Realtor mom and always heard that they were rat-friendly), so I thought I was in the clear with my own yard. Not so. I have climbers and star jasmine. We have fruit trees and usually only pick up the fallen fruit once a week. Apparently that’s all bad!! My neighbors have bamboo. Other neighbors have juniper and Italian cypress.

It’s important to keep rats, mice, squirrels, and all sorts of creatures off of your roof. Some animals are skilled climbers, but in general they will make use of things such as branches hanging over the roof to get up there. We once had a squirrel get onto our roof and claw a hole in some of the flashing there, causing the rain to come in.

The Vector Control brochure makes a point that for rats to inhabit an area, they need food, water, and a home, or rat harborage, as the pamphlet says). By eliminating the type of plants which provide harborage and food, we can reduce the risk of a rat invasion. After my neighbor’s experience, I think that’s a plan worth implementing!

Keeping rats out of your garage and house

Rats may prefer your garage, crawlspace, attic, or interior walls to the great outdoors, which is far more dangerous for them as hawks and other predators have better access. It does not take a very big opening for them to get in. It’s imperative to make sure that the vents to the foundation and attic have no gaps or holes and that the doors into the garage do not feature any gaps big enough for them to enter.

Rat abatement

If rats have gotten into your home or yard, in most cases it would be wise to employ a pest control company to help with the exclusion work as well as trapping and removal work. Exclusion refers to finding and eliminating the access points into you condo, townhouse, or house, such as a tear in a foundation vent screen.

Not every pest control company does rat abatement. The rodent jobs are “branch two” types of licensed work. Several companies in our area provide this type of service. Often the cost is between $500 and $1,000 (but not always).

This does not include the removal of droppings or disinfecting after the pellets have been removed. That’s a different service and company. The droppings can create a health hazard, so I would strongly suggest hiring a professional for this type of job.

Raccoons and other animals

Andy with Creature Catchers making our resident raccoon decide it was time to move awayThe pest control companies don’t address problems with raccoons, possums, skunks, or other animals. If you need help with them, I can wholeheartedly recommend Andy with Creature Catchers.

We once had a mama raccoon get into the roof over our front courtyard archway (luckily, it did not connect to our home or garage attic) and make a nest there with her babies. Andy’s clever work convinced her that this was not a cozy home, and that very night she relocated herself and her kits elsewhere. We were glad of that as we didn’t want to imagine the alternative.



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