- (Focus Area) Pest Management
- Author: Kathy Keatley Garvey
So there you are, admiring your Coreopsis and suddenly you notice spots and holes--spots on the backs of two western spotted cucumber beetles, and holes cut in the petals.
Ah, there's two of them.
The beetles, about a fourth of an inch long, are fun to photograph, but they're not your buddies. Nor would they want to be!
"Cucumber beetles are very common pests in vegetable gardens and may also attack ripening stone fruit," says the UC Statewide Integrated Pest Management Program. "The most abundant species in California is the western spotted cucumber beetle, Diabrotica undecimpunctata...The western spotted cucumber beetle is greenish yellow and has twelve black spots on its back."
Ever counted the spots? Yes, 12.
We've seen the beetles feeding on the leaves of flowers and many vegetables. "Cucumber beetles may also spread cucumber mosaic virus or wilts in cucurbits," UC IPM says. "Larvae feed exclusively on roots, but do not generally damage garden plants, although corn may occasionally be damaged."
Spotted cucumber beetles don't move very fast early in the morning, so they're fairly easy to photograph.
And sometimes you get a "two-fer," two in the same image. 24 spots.
![Two Western spotted cucumber beetles, Diabrotica undecimpunctata, on a Coreposis. (Photo by Kathy Keatley Garvey) Two Western spotted cucumber beetles, Diabrotica undecimpunctata, on a Coreposis. (Photo by Kathy Keatley Garvey)](/blogs/blogcore/blogfiles/108338.jpg)
Fleas can be found on pets year-round, but populations tend to increase dramatically in spring and summer when temperatures are warmer. Larvae develop rapidly in areas where temperatures reach 70° to 90°F. Fleas are a major concern for pet owners as they can give dogs and cats tapeworms, but they can also transmit flea-borne typhus to people and spread plague to wild animals like ground squirrels. These blood-sucking pests can be introduced to backyards from feral cats, squirrels, opossums, and other wildlife.
To learn more about fleas, the diseases they can spread, and their management, check out the recording of UC IPM's Urban & Community IPM Webinar from June 2024 at https://www.youtube.com/watch?v=b-w7J6mkTeM. You'll hear from flea expert Dr. Laura Krueger of the Orange County Mosquito and Vector Control District on how you can protect yourself and pets from fleas.
- Author: Elizabeth J Fichtner
Mireya Molina, a rising senior at El Diamonte High School, joined UCCE Tulare County as a 2024 summer research intern serving the nut, olive, and prune research and extension program. Mireya has a strong science background and is an active member of her high school horticulture and FFA programs. She has served as a volunteer at fundraisers for the local SPCA and at Happy Trails Riding Academy as well as at a youth science fair hosted by the Visalia Unified School District. Mireya has taken advantage of the AP and agricultural education coursework at El Diamonte High School and expresses an interest in pursuing a BS in animal science at Chico State University in fall 2025. During the summer of 2024, Mireya served as a volunteer intern in the research and extension program of Elizabeth Fichtner, UC ANR Farm Advisor, working on enumerating insects for a pest management study on walnuts. Mireya's work contributes to the understanding of the best timing for application of insect growth regulators (IGR) for management of walnut scale, specifically determining the value of dormant applications versus delayed dormant application of Centaur®, an IGR produced by Nichino America. Her work will help walnut growers gain the maximum value out of each application of the insecticide, thus reducing overall insecticide inputs for management of the pest.
![Mireya Molina, El Diamonte High School Student, serves as summer intern Mireya Molina, El Diamonte High School Student, serves as summer intern](/blogs/blogcore/blogfiles/108260.jpg)
- Author: Lauren Fordyce
Are you noticing an abundance of cobwebs outside, on plants, fences, homes, or outdoor furniture?
While many people fear spiders or dislike their cobwebs, most spiders are beneficial to have around– even in the home! Spiders are predators of many insect pests and rarely cause harm to people. The only medically significant spiders in California are brown and black widows. While these spiders have the potential to cause harm, it is rare that they will bite, even in areas where they are very common. Like most spiders, they prefer to stay hidden and avoid people.
Some common web-spinning spiders you might encounter outdoors include:
- Funnel weavers: feed during the day and night near the ground in most types of vegetation, including low-growing plants and trees. Spin funnel-shaped webs, often with several-inch-wide, flat extension covering plants or soil.
- Sac spiders: spin silken tubes or sacs under bark, among leaves, and in low plants or on the ground, where they hide during the day or retreat after hunting. They are typically nocturnal, medium-sized, pale spiders with few markings.Female sac spider or twoclawed hunting spider with her eggs. Photo by David Rosen.
- Garden spiders: feed on insects that fly, fall, or are blown into their web. Elaborate silken webs are spun in concentric circles.
- Dwarf spiders: prey on insects that fall, walk, or land in their web. They are diurnal (day active) spiders found in the plant canopy and among litter on the ground. Dwarf spiders produce sheetlike webs on the surface of plants or soil.
- Comb-footed spiders: feed on insects that walk or fly into their webs. They almost always are found hanging upside down by their claws in irregularly spun, sticky webs, waiting for prey. Generally they have a soft, round, bulbous abdomen and slender legs without spines.
Unwanted cobwebs can be swept, mopped, hosed, or vacuumed up. Insecticides should not usually be used against spiders outdoors and don't provide good control anyway.
For more information about spiders in and around the home, visit the Pest Notes: Spiders.
- Author: Daniel K Macon
Folks new to the world of working livestock guardian dogs (LGDs), whether they are producers or dog aficionados, often ask, “What's the best breed?” or “What breed is your dog?” I usually begin my answer with a joke: “He's a North American BWD – Big White Dog!” I then go on to explain that all of my successful dogs have usually been a mix of breeds, and that I put more emphasis on the working abilities of my dogs' parents and on desirable phenological traits (like a short coat) than I do on selecting specific breeds. My most recent dogs have all been mixes – Maremma-Anatolian, or Pyrnees-Akbash, for example. And I suspect that most working LGDs here in North America are not purebred – dogs that work in a production setting are also those who get to reproduce, regardless of whether they are purebred. Sometimes this breeding is intentional! A new paper published in iScience sheds light on the varied ancestries of modern livestock guardian dogs.
In “Multiple ancestries and shared gene flow among modern livestock guarding dogs,” the authors generated genome-wide single nucleotide polymorphism (SNP) data from 304 LGDs and combined it with public-genomic data from 2183 modern and 22 ancient dogs. Their analysis suggests shared ancestry and extensive gene flow among modern LGD breeds, which they attribute to historic livestock migrations.
The authors developed genome-wide SNP data from specific LGD breeds extended geographically from the Iberian Peninsula, through Europe, Italy, the Balkans, Western Asia, and Eastern Asia. While much of their analysis goes beyond my very simplistic understanding of genetics, their findings “strongly support the hypothesis that modern LGD breeds from East Asia and the rest of Eurasia are part of two lineages that have evolved independently for millennia.” I find this fascinating – humans who were raising livestock on rangelands in separate regions of the planet looked to dogs as protectors of their livestock! And they developed separate genetic lines with similar physical and behavioral traits!
Transhumance migration – the seasonal movement of people and livestock between high- and lowlands (following the feed) – seems to have played a significant role in the genetic flow between regionally-specificLGD breeds.Transhumance seems to have occurred across many cultures and geographic regions (and still persists today). The nomadic herders of the Mongolian steppes and the open-range sheep outfits of theIntermountain West would recognize eachother's day-to-day work.
Similar to today's Big White Dog breeding strategies, I can imagine multiple family groups taking their sheep and goats along adjacent (or overlapping) migration routes into (and back from) the high country. Perhaps my modern notions of livestock ownership doesn't exactly apply, but I suspect that each family would have tried to keep their livestock separate from the adjacent flocks. But the dogs would have mixed on the margins between these flocks! And they would have reproduced.
In his essay, “Let the Farm Judge,” Wendell Berry describes the powers of observation and adaptation employed by thousands of shepherds over thousands of years on the British Isles that allowed the development of 80 distinct sheep breeds and cross-breeds on a group of islands smaller than California. I can imagine similar observations and adaptations leading to LGD breeds in a transhumance system of livestock production. The dogs that stayed with their flocks – that protected livestock from wolves, brown bears, big cats, other dogs, and even 2-legged human predators – were noted by their owners. And allowed to reproduce – either with other dogs guarding the same flock, or with dogs guarding adjacent herds. If the offspring of these couplings didn't work, they left the gene pool.
The paper notes that reproductive management has not always been intentional in LGD breeds (nor is it today, for that matter). The authors' genetic analyses suggest that there is ongoing gene flow between LGD breeds and free-ranging dogs in specific geographic regions, stating, “Whereas breed clubs and registering bodies forbid dog owners from crossbreeding to dogs from other breeds for the purpose of maintaining traits, such restrictions are not imposed on working landrace populations and, as such, may be challenging to maintain in working dogs frequently left unattended.” In other words, dogs will be dogs – especially LGDs!
Finally, the authors discuss the relatively recent transition of some LGD breeds from working landraces to a registered system of pedigreed pets (notably the Great Pyrenees and Kuvasz breeds). In comparing pet dog genetics with those of working lines, the authors found a higher degree of inbreeding in pet dogs, likely reflective of the use of a handful of popular pedigreed sires.
These last two findings, as the authors indicate, suggest that selecting LGDs for specific guarding behaviors (attentiveness to surroundings, lack of prey drive, or submissiveness to livestock) and other factors (likelihood of roaming, or lack of aggressiveness towards people) may not be entirely (or even mostly) genetically based. In other words, reproductive isolation (that is, only breeding working LGDs to other working LGDs) may not the core mechanism for maintaining the specialized skills of LGDs. Assessing the behavior and performance of a prospective LGD during the puppy selection process becomes even more critical, given these findings – as does the bonding process. While I'm not suggesting that a well-managed bonding process will overcome poorly bred LGDs, this paper seems to confirm that genetics is just one part of a very complicated puzzle! It was a fascinating read!
Coutinho-Lima, D., et al., "Multiple ancestries and shared gene flow among modern livestock guarding dogs." iScience. 110396. August 16, 2024.