The mild fall temperatures continue to be great for outdoor barbecues, but family and friends are not the only guests gathering at the picnic table. Also coming to dinner are yellow jacket wasps and honeybees. In search of a late-season meal, these invaders can be bothersome, to say the least. So take care to inspect your food and drink before every bite, or you may wind up with more than a mouthful. Here is what you need to know about these aggressive visitors and how to keep from getting stung at your next outing:

Yellow jackets are small black and yellow wasps that usually build their nests underground or in rock walls, old hollow tree stumps or other areas where they are protected from the elements. These social creatures usually have one queen and up to several thousand workers in a single colony. They are quite aggressive and can chase an intruder several hundred yards before retreating home.

They mainly feed on meat scraps, pollen and sugary substances, such as nectar from flowers. However, as the days get shorter and the flowers are less plentiful, these scavengers start looking for a meal elsewhere – mainly at your picnic. Take time to seal up trash cans and other potential food sources. Likewise, look twice before sipping from a soda that has been sitting on the picnic table for more than a few minutes. All of these can be potential food sources for hungry yellow jackets.

Controlling these creatures is not easy. The nest must be located and destroyed. Approach the nest at night with the light of a flashlight covered with red cellophane. Thoroughly saturate the area with a liquid insecticide and quickly cover the hole with a shovel of dirt. Repeat treatments may be needed.

Usually considered a dedicated worker in the vegetable or flower garden, honey bees can be serious pests this time of year as well. Honey bees are a more stout, sturdy-looking insect than yellow jackets. They are about a half-inch long, brown with golden brown markings, fuzzy hair and pollen sacks on their hind legs.

Because flowers, their natural food source, are starting to decline, trash cans, spilled sweets or rotting fruit can become feeding sites for robbing honey bees. Proper sanitation is the first step to discouraging these visitors. Use a mild detergent and large amounts of water to regularly clean up areas in which syrup or other sugars are frequently spilled. Likewise, use plastic can liners and tight-sealing lids for trash cans and other food storage areas. A few bees that discover a readily available sugar source can recruit a large number of friends in a short period of time.

As a last step, in the orchard or vegetable garden, clean up damaged, dropped or overripe fruit as much as possible. As they ferment, they become more tasty to the hungry hive.