From our perspective as Columbine plants (genus Aquilegia), we must address the reality that our foliage and flowers are, unfortunately, quite palatable to several herbivores. Our leaves are tender, especially in the spring, and our unique, nectar-rich flowers are attractive. While we have developed certain defense mechanisms over millennia, they are not foolproof. Deer, in particular, are opportunistic browsers. When preferred food sources are scarce, they will not hesitate to consume our entire above-ground structure—leaves, stems, and blossoms. A single deer can decimate a large planting in one night. Rabbits, being lower to the ground, are more likely to nibble on our tender young shoots and seedlings, often severing them at the base.
We are not entirely defenseless. Our primary evolutionary strategy is our toxicity. We produce cyanogenic glycosides—chemical compounds that can release cyanide when our tissues are crushed and digested. This is a potent deterrent against many insects and mammals. For most creatures, consuming a large quantity of our foliage would cause poisoning. However, deer and rabbits have digestive systems that can sometimes tolerate small amounts of these toxins, especially when other forage is unavailable. Furthermore, the level of toxicity can vary between species and even individual plants, influenced by soil conditions and climate. It is our best defense, but it is not an absolute guarantee of safety.
Our relationship with the animal kingdom is complex and dualistic. While deer and rabbits pose a threat to our physical structure, other animals are absolutely vital for our survival and propagation. Our uniquely shaped flowers, with their long spurs, have co-evolved with specific pollinators like hummingbirds, hawk moths, and bumblebees. These creatures are essential partners, transferring pollen from one plant to another and ensuring genetic diversity and seed production. Deterring all animals is not a viable strategy for us; we must walk a fine line, repelling some while actively attracting others. This is the central challenge of our existence.
When a deer or rabbit consumes our flowers, the immediate impact is the loss of that season's potential for seed production. This is a significant setback, as reproducing is our primary biological imperative. More critically, if an animal repeatedly browses our foliage, it depletes our energy reserves stored in our roots. We are perennial plants, relying on photosynthesis throughout the growing season to build up strength for the next year. Severe or repeated browsing weakens us considerably, making us more susceptible to disease, pest infestation, and winter kill. It can drastically shorten our lifespan and our ability to form large, thriving clumps over time.
The threat posed by deer and rabbits is not constant. It fluctuates greatly based on geography, season, and local ecosystem dynamics. In areas with high deer population density and limited natural forage, we are at much greater risk. In spring, when our new growth is most tender and other food sources may still be limited, we are particularly vulnerable. During a drought, animals are more likely to eat plants they would normally avoid due to lower moisture content in other vegetation. Conversely, in a lush, biodiverse habitat with abundant alternative food choices, we may be left relatively untouched, as deer and rabbits often favor other plants over us if given the option.
