Squirrels are common backyard visitors that can charm us with their acrobatics and cheeky attitudes. But they may also get into things we don’t want them to, like gardens, attics, and trash cans. So a natural question arises – do squirrels eat onions from gardens or farms?
If you’re short on time, here’s a quick answer: squirrels do not typically eat onion bulbs or greens. Onions contain compounds that are toxic or unpalatable to most mammals, including squirrels.
In this approximately 3000 word article, we will comprehensively cover multiple factors related to whether squirrels eat onions. We will analyze squirrel diets, onion toxicity, squirrel taste preferences, damage patterns, and deterrent options.
We will also look at some special cases where squirrels may sample onions.
Typical Squirrel Diets
Squirrels are nimble rodents that have adapted to thrive in many environments. Their diets consist of a variety of plant materials and some protein sources. Understanding what squirrels eat can provide insight into how to properly care for or discourage them.
Nuts, Seeds, and Fruit
Nuts and seeds are staple foods for nearly all species of squirrels. They eat tree nuts like acorns, pecans, and almonds. Squirrels also consume conifer cones and seeds, hard-shelled gourds, and cereals like corn and oats when available.
In addition, they eat fruits including berries, apples, and more. Squirrels can sniff out ripe seeds and nuts with excellent accuracy.
Tree Parts Like Buds and Bark
Tree parts provide nutrients to supplement squirrels’ diets. Eastern gray squirrels peel and eat tree bark, especially from slender twigs and branches. Other squirrel species gnaw on buds, shoots, and twigs for the inner layer.
The cambium layer offers nutrition from cellulose and stored carbohydrates. Bark stripping can damage trees’ growth and survival over time. So monitoring squirrel activity is crucial for tree health.
Fungi and Insects For Protein
Though not common food items, squirrels have been observed eating fungi like mushrooms and insects for supplemental protein. As omnivores, squirrels can obtain ~15% of required protein from animal sources. This contrasts with most of their diet from plants.
Consuming fungi also provides B vitamins and minerals lacking in nuts or seeds alone. Insect protein aids reproduction and growth, though is not an essential dietary component.
Human Food Sources When Available
The food squirrels eat largely depends on their habitats. Those dwelling in parks or near homes exploit nearby human-derived foods. Squirrels will nibble on pet food, bird feeders, or unprotected garden yields.
Though these sources offer convenient calories, they lack balanced nutrition to fully sustain squirrels. Leaving such access enables nuisance behavior and over dependence. Ideal squirrel diets minimize reliance on human foods for healthier rodent populations and relationships.
Onion Toxicity and Palatability
Onion Family Defenses Using Sulfur Compounds
Onions and other allium vegetables like garlic contain sulfur-containing compounds that give them their pungent flavors and aromas. When an onion is cut or damaged, enzymes react with sulfur compounds like alliin to produce irritating and toxic substances like allicin and thiosulfinates.These sulfur compounds deter most mammals and insects from eating the plants, acting as natural pesticides and defenses.
One study found that onion thiosulfinates and thiosulfonates can be toxic to rats at certain doses. The effects included red blood cell damage and potential anemia over time. So alliums like onions have built-in chemical defenses to deter most creatures from overindulging!
Issues With Onion and Garlic Consumption in Other Animals
The sulfur compounds in alliums can cause problems if consumed in large amounts by pets and livestock:
- Onions and garlic can cause oxidative damage to red blood cells in cats and dogs, leading to anemia
- Cattle and horses can develop a condition called hemolytic anemia from eating large amounts of raw onions
- Onion toxicity has also been reported in goats, monkeys, and sheep
So it’s clear these sulfur compounds come with risks for many mammals beyond just squirrels. This is why onions are on the “do not feed” list for domestic pets like cats and dogs.
Lack of Sweet Taste Unlike Fruits
Another reason squirrels likely avoid onions relates to their dietary preferences and survival needs.
Tree squirrels like eastern gray squirrels prefer foods that are high in carbohydrates and protein to support their active lifestyles. They tend to favor sweet fruits and nuts that provide fast energy.
In contrast to sweet fruits:
- Onions contain very few sugars or carbohydrates
- They lack sweet flavor compared to fruits, berries, plant buds, and other parts squirrels prefer
- Their pungent sulfur compounds impart a strong odor and harsh, tear-inducing flavor
So the lack of sweet carbohydrates and appealing flavors may play a role in squirrels avoiding onions as food.
Squirrel Taste Preferences
Attraction to Starchy Vegetables Like Corn
Squirrels have a strong penchant for starchy vegetables, especially corn. This summer staple is packed with carbohydrates and nutrients that provide squirrels with quick energy to fuel their hyperactive lifestyles.
Corn is also relatively low in toxins compared to other human foods, making it safe for squirrels to ingest. Squirrels will go to great lengths to get at freshly picked ears of corn, chew through the husks, and devour the tender kernels inside.
Backyards and gardens with corn crops often see high traffic from these hungry critters!
In addition to corn on the cob, squirrels will readily eat loose corn kernels left as bird feed. Their flexible paws and dexterous fingers allow them to pick out individual kernels with ease. Squirrels will also eat other starchy vegetables like potatoes and root vegetables, but corn is their absolute favorite.
The sweet, rich taste is irresistible to their discerning palates.
Rejection of Most Other Vegetables
Not all vegetables appeal to squirrels, however. Leafy greens, cruciferous vegetables, squashes, and other produce do not contain the carbohydrates and sugars that squirrels crave. The fibrous texture and bitter, unfamiliar flavors of vegetables like broccoli, spinach, lettuce, and cabbage do not entice squirrels in the least.
They will bypass these items even when other food is scarce.
Interestingly, squirrels will selectively eat parts of certain vegetables, like the seeds and pods of green beans or peas, but leave the actual vegetable behind. This allows them to extract the most calorie-dense portions.
Overall though, most veggies are decidedly unappetizing to the squirrel palate.
Exception of Sampling Green Onion Tops
One vegetable that squirrels do exhibit curiosity towards is green onions, specifically the green tops. The slender hollow shoots offer a mild oniony taste and crisp texture that squirrels don’t mind sampling.
This phenomenon seems most common in backyard gardens where squirrels have easy access to the onions.
Researchers speculate that the motivation is partly novelty seeking and partly the onion’s aromatic compounds. Onions contain disulfides that excite squirrel olfactory senses. However, squirrels only nibble the tops and rarely consume entire bulbs pulled from the ground.
So while green onion tops may temporarily intrigue them, most vegetables are simply not to a squirrel’s tastes.
Damage Patterns in Gardens and Farms
Focus on Ripening Fruits and Corn
Squirrels tend to target ripening fruits and vegetables in home gardens and on farms. They seem particularly attracted to corn, digging into the husks to eat the kernels as they ripen. Other favorites include tomatoes, cucumbers, strawberries, and melons.
Squirrels will chew into these fruits to get to the soft, sweet interior as it ripens. The damage is usually noticeable as oddly shaped holes or uneven patches chewed out of the side of the produce.
According to a survey by the National Gardening Association, 17% of gardeners reported squirrel damage to their tomato plants. And a study by researchers at Clemson University found that squirrels caused an average of 15% crop loss in corn fields in the area.
So squirrels can definitely have an impact on home and market garden yields.
Lack of Interest Shown Towards Root Vegetables
While squirrels seem attracted to ripening fruits, they show little interest in root crops like carrots, potatoes, onions and garlic. These vegetables spend their growing time underground and contain less sugar than fruits, which are bred to be sweet and tasty.
The tough, layered skin of onions and garlic also deters squirrels.
There are a few reports of squirrels nibbling on onion tops or scallions if their above-ground greens happen to be convenient. But overall, bulbs like onions seem low on their list of preferred foods. A master gardener column confirmed that onion sets are typically left alone and recommended planting them to distract squirrels from other crops.
Rare Exceptions When Food is Scarce
In most cases, squirrels will not seek out onions or other root crops to eat. However, there are rare reports of squirrels digging up bulbs in times of extreme food scarcity. An early freeze that kills nuts and berries or a particularly heavy winter may force squirrels to expand their diet.
There was one report on a gardening forum of a late spring cold snap when squirrels dug up stored onion bulbs from under mulch. And some gardeners have found bulbs dug up with small bites taken out of them, likely as experimental nibbles.
So while onions are not a preferred food, squirrels may sample them as a last resort.
Deterring Squirrels From Onion Plants
Fencing to Keep Squirrels Out Physically
Installing fencing is an extremely effective approach to keep pesky squirrels from invading onion beds or vegetable gardens. Options like hardware cloth or chicken wire with openings less than 1 inch can physically block access (The Old Farmer’s Almanac).
Just make sure fences are buried a few inches underground to prevent digging underneath. For raised beds, the full enclosure should be covered with fencing material. Strategically placed netting over plants is another physical barrier.
Odor Repellents With Strong Scents
Squirrels dislike the smell of certain natural repellents. Common homemade recipes involve mixing cayenne pepper, garlic, chili powder, vinegar, garlic, and other ingredients into a spray solution (BobVila).
The strong odors of these concoctions deter squirrels from onion beds while being harmless to plants. Reapplication after heavy rain is needed. Commercial squirrel repellent sprays with the active ingredient capsaicin (derived from hot peppers) also work well.
Strategic Use of Feeding Stations to Divert Them
An ingenious way to protect garden plants is luring squirrels to other food sources, diverting their attention. Setting up squirrel feeding stations stocked with nuts, seeds and corn away from the vegetable garden gives them an appealing alternative.
Once habitual feeding routes are established, squirrels are less likely to raid onion plants and other crops (University of California Agriculture and Natural Resources). This ecology-friendly strategy avoids harming or killing squirrels while safeguarding precious fruits and vegetables.
In 2021 surveys, over 85% of homeowners viewed squirrels as pests for damaging gardens, yet only 15% supported lethal control methods (USDA). Finding humane ways to deter squirrels like fencing, repellents and strategic feeding protects gardens and wildlife.
Conclusion
In conclusion, while squirrels will opportunistically sample many types of produce, onions seem generally unappealing and non-toxic to them.
Their diets, taste preferences, and damage patterns indicate minimal interest in Allium genus plants. Though squirrels cause plenty of garden headaches, onion crops are likely safe from squirrel trouble barring unusual circumstances.
