The homeowner can help control rat populations by doing the following:

• Harvest oranges, grapefruit, apricots, plums, nuts, tomatoes, etc. as soon as they are ripe. Pickup up all fruit that has fallen on the ground.
• Never leave uneaten pet food outside overnight. Keep pet food in sealed, metal containers if stored in the garage or other outbuildings
• Keep plum trees and yucca plants well-trimmed. Algerian ivy, oleander, bougainvillea, jasmine, and other thickly matted plants should be periodically thinned and trimmed well away from roofs, walls, fences, utility poles, and trees.
• Store wood and lumber piles on racks at least 18 inches above the ground and 12 inches away from walls.

Rats can enter a home through small exterior openings of less than one inch in diameter. Important steps a homeowner can take to exclude rats are inspecting and repairing:

• Basement windows and ventilation ports
• Attic vents and louvers
• Gaps between roof and chimney
• Vent pipes and shafts
• Tile roofs along the eaves

All-access openings should be screened with 1/4 inch galvanized hardware cloth and inspected at least once a year for the condition. Gaps around pipes and electrical conduits should be sealed. Tree limbs should be kept well away from the eaves, roof, and exterior walls of the house