Tuleyome's Science Corner - Paper Wasps and Yellowjackets

Kristie Ehrhardt • September 21, 2023

Paper Wasp and Nest

The Sacramento region is home to at two very common types of social wasps (wasps that live together in a community); paper wasps and yellowjackets. Both yellowjackets and paper wasps belong to the family Vespidae which contains about 1,100 species. Yellowjackets belong to the subfamily Vespinae which contains two genuses (Vespula and Dolichovespala). Paper wasps belong to the subfamily Polistinae which contains approximately 300 species worldwide, 22 of which are in California and belong to the genus Polistes.


Yellowjackets and paper wasps are commonly confused and misidentified because they look quite similar, however there are some notable differences if you don’t mind getting pretty close to them. Yellow jackets are typically black with yellow markings, are slightly less than an inch long and appear chunkier lacking the very tapered “wasp waist” that paper wasps display. Paper wasps are slightly bigger than yellowjackets, dark brown with yellow markings and have orange-tipped antennae and long rear legs that dangle behind them in flight. Both yellowjackets and paper wasps build nests out of paper which consists of chewed plant material, wood and saliva. Both begin nest construction which is made of rows of individual hexagonal cells in the early spring as the weather warms and the queen has emerged from hibernation. Depending on the species, yellowjacket nests can be underground often in abandoned rodent burrows (sometimes this species is called “meat bees”) while other species build a suspended nest from a structure or inside the walls of a building. Generally, yellowjacket nests they are much larger than paper wasp nests as the colonies can host many thousands of individuals and ends of the cells are sealed with a paper envelope so the embryo is not visible. Paper wasp nests are smaller with open hexagonal cells and they are always attached to a structure by a small stalk or pedicel and look like a tiny, hanging umbrella. Some species of paper wasps manufacture a chemical that keeps ants from crossing the pedicel and accessing their larvae. Colonies of paper wasps are much smaller and may only support 100 to 200 individuals. Rather than build a single large nest, paper wasps use several nest sites which may include the eaves of a house or shed, outdoor birdhouses, benches, grills and other outdoor structures and shrubbery.


I recently learned most wasp species, yellowjackets and paper wasps included, play an important role in biological pest control. In the early spring as wasp colonies are growing, they prey on species that impact crops such as caterpillars, aphids, beetle larvae and flies. In late summer and early fall the colonies forage on nectar to feed the queen and workers. As a result, they are also important pollinators. It is also this time when yellowjackets and wasps may come into more frequent contact with humans by swarming around trash cans, barbecues and even open soda cans looking for sweet things.


Generally speaking, paper wasps are shy of humans, far less defensive and much less prone to sting unless their nests are disturbed. Yellowjackets are more irritable and aggressive and seem to almost want to pick fights with humans. Like all wasps, both species can sting multiple times and although not common, anaphylactic reactions can occur. Studies have shown that some species that display brighter colors have larger venom glands and as a result are more venomous. It’s thought that the brighter color is a warning to keep predators away from the nest.


The Sacramento-Yolo Mosquito and Vector Control District website states that it is dangerous to confront a yellowjacket nest and they offer free help with nest removal. They can be contacted here for more information.


-Kristie Ehrhardt (kehrhardt@tuleyome.org)

Tuleyome Land Conservation Program Manager


RECENT ARTICLES

Beavers, otters, and more – new Conaway Ranch game camera footage!

By Geoff Benn • June 4, 2026
A beaver at Conaway Ranch We’ve got new footage from our game cameras at Conaway Ranch! This camera site was chosen by 4 th graders from Dingle Elementary during a recent field trip to Conaway. The camera is near the otter slide we’ve previously filmed, but is a few feet away from the entrance to the slide, allowing us to film the animals as they approach. We saw beaver, otter, a fox, a raccoon, and more! Click here to watch the video . Tuleyome works with Conaway Preservation Group to offer educational programs at Conaway Ranch, including programs for K-12 groups and the general public. If you have any questions about the game camera footage or our programs at Conaway, please reach out to Education Associate Geoff Benn at gbenn@tuleyome.org.

Policy Corner: It’s Time to Fight for Our Public Lands

June 4, 2026
The current administration has released its proposed budget for the 2027 fiscal year. It proposes drastic cuts to our public land management agencies. The proposed budget would significantly reduce funding for the Bureau of Land Management (BLM), including a 34% cut to its total budget, a 27% staff cut, a 76% cut to the National Conservation Lands, which encompass 38 million acres of protected public lands, a 61% cut to recreation management (including campsites and trails), and total elimination of funding for cultural resources and wilderness management. It also would shift priorities towards extractive uses of public lands instead of conservation and clean energy. The administration’s budget would also drastically cut funding to the U.S. Forest Service (USFS), eliminate several offices, state and federal research stations (six in California) and transfer all fire fighting to BLM. Notably, in the face of all these cuts, the budget would increase funding for extractive industries; funding for timber sales would increase 450%. The reductions and policy changes would impair these agencies’ abilities to protect public lands, cultural resources, fresh water sources, and wildlife, while also impairing access to them and recreation on them. The President’s budget is now in Congress, where committees in both the Senate and the House of Representatives are amending and voting on the bills in preparation for full House and Senate votes. Now is the time to take action for our public lands and the environment by urging Congress to reject the proposed budget and maintain funding for BLM, USFS, and programs that protect and steward our public lands. Let your representatives know that you oppose the cuts to BLM and USFS and the rollbacks to our public land protections. And let them know why these special places are important to them. You can voice your opinions to Congress in multiple ways. You can: Call their offices Send a letter to Congress - we’ve pulled together a template for you to use, but don’t forget to let them know why public lands are important to you – download sample letter here Contact them on social media Meet with a representative in their District offices. Don’t know how to reach them, go to Congress.gov and find their phone numbers, addresses, district offices, websites and so much more if you’re interested. Now is the time to speak up for our public lands! Mary Lamborn (Communications Intern) and Sandra Schubert (Executive Director)

Monumental Questions - Another Monumental Vegetable?

By Kristie Ehrhardt • June 4, 2026
You betcha! Wild carrot, also known as Queen Anne’s Lace, is a common site within the Berryessa Snow Mountain National Monument region. With its straight and sturdy stalk, bright green, frilly leaves and white, flat-topped flower clusters, it is identifiable even from the limited viewing scope of a traveling car. Queen Anne’s Lace ( Daucus carota ) belongs to the Apiaceae (carrot) family. All members of this family display flower clusters arranged in an upside-down umbrella shape called an umbel. It is native to Europe and is the plant that tasty cultivated carrots originated from. It was brought to North America for its medicinal purposes and has since naturalized across the continent in disturbed and natural areas in mountains, valleys and coastal areas. It can be so prolific that it outcompetes native plants and can also be mildly toxic to livestock. Queen Anne’s Lace is an herbaceous biennial (it doesn’t flower until its second year and then dies) that can reach up to four feet tall in optimum conditions. The stem of the plant is bright green, straight and sturdy and is covered in short, coarse hairs which is a very helpful identifier. I recently learned a clever and helpful quip that I will never forget: Queen Anne has hairy legs (referring to the hair along the stems of the plant)! The tiny, white flowers all originate from the same point and splay out in an airy, flat topped cluster (umbel). Another identifying feature is that oftentimes (but not always) the flower umbels often have a single dark purple flower in the center of the cluster. This purple flower is not always present but when it is it can be used to positively identify the plant as Queen Anne’s lace. The leaves are finely divided which gives them a lacy appearance and look almost identical to our cultivated carrot plants. Although wild carrots are edible, the whitish tap root isn’t as robust or flavorful as the cultivated carrots we are used to. Warning! There are plants such as poison hemlock that are incredibly similar looking so eating things in nature is never advised unless you can absolutely identify them! Poison hemlock has basically the same growth pattern as wild carrot however the stem of poison hemlock lacks the tiny hairs and mature plants have very definite purple splotches up and down the stems. All parts of poison hemlock are toxic but it is particularly potent in the seeds and roots. Poison hemlock is notoriously known as the poison that killed the Greek philosopher Socrates. Edible cousins of wild carrot include plants such as caraway, celery, parsley and parsnips. Although the root of the wild carrot plant is edible, contact with the sap may produce an allergic reaction in some individuals that are sensitive to it. Native pollinators such as butterflies and bees appreciate the abundance of flowers for their nectar. Wild carrot is currently blooming in all its glory so keep an eye out for it on your next trip to our favorite monument!