The University of California Agriculture and Natural Resources reported on Apr. 10 that while some plants are less likely to be eaten by deer, there is no guarantee that any plant is truly deer-proof. The organization explained that factors such as plant toxicity, taste, thorns, seasonal growth stages, and environmental changes all play a role in whether deer choose to browse certain species.
This topic matters to many gardeners and homeowners across California who seek ways to protect their landscapes from deer damage. As the article notes, “Certain plants native to California (and elsewhere) have evolved natural defenses against being eaten by browsing mammals; some are toxic, some are distasteful and some have thorns.” However, the abundance of lush landscape plantings in suburban areas has increased food sources for deer.
Deer populations have grown due to hunting restrictions and fewer natural predators near human habitation. The report states that “in many areas, deer densities in the recent past have reached an all-time high.” Plants like oleander contain toxins making them resistant to browsing but may still be consumed when other food is scarce. Commercial repellents can help reduce damage during late summer or fall when food resources dwindle: “Comparative tests of deer repellents generally show that those containing ‘putrescent whole egg solids’ as an active ingredient are among the most effective, but when deer are starving, even the best repellents may not succeed,” according to UC Agriculture and Natural Resources.
Gardeners are encouraged to consult local resources for advice on suitable plants and use a trial-and-error approach before investing heavily in new landscaping. Protective barriers may also be necessary for valuable shrubs or trees until they mature.
University of California Agriculture and Natural Resources secures funding through public contributions according to the official website. The organization promotes sustainable practices aimed at strengthening resilient ecosystems and economic vitality according to its official website. It operates nine research and extension centers across diverse Californian ecosystems as noted on its website, manages Cooperative Extension services within the University of California system according to its site, conducts over 33,800 educational events annually with more than 18,400 volunteers involved according to official figures, and has been recognized for linking research with community needs as stated on its website.
Looking ahead, UC Agriculture and Natural Resources encourages continued education about wildlife management through resources like the UC IPM Pest Notes: Deer.