Do Cicadas Devour Your Garden?

Have you ever wondered if those noisy, periodic visitors to your garden, cicadas, could be causing any harm to your beloved plants? While it's true that these insects can be quite a nuisance with their loud buzzing and sudden appearance, the extent of damage they cause to garden plants is often overestimated.

Cicadas are fascinating creatures that undergo a complex life cycle, spending most of their lives underground as nymphs before emerging as adults. They feed primarily on sap from tree roots during their nymphal stage and on sap from tree branches and leaves once they've emerged. This feeding behavior has led some gardeners to worry about the potential damage cicadas might cause to their plants.

Cicadas' Diet and Feeding Habits

Cicadas are sap-sucking insects, belonging to the order Homoptera. They feed on sap from plants, which they extract using their piercing-sucking mouthparts. This sap is primarily composed of water and sugars, providing cicadas with the energy they need to grow and reproduce.

While cicadas do feed on a wide variety of plants, they are not known to be particularly selective. They have been observed feeding on both native and non-native plants, including trees, shrubs, and even some herbaceous plants. However, their preference is generally for larger plants, as these provide more sap and are easier to feed from.

Root Feeding by Cicada Nymphs

During their nymphal stage, which can last for several years, cicadas feed on sap from the roots of plants. This feeding can potentially weaken plants, especially if the infestation is heavy. However, it's important to note that cicadas are not typically considered a major pest of garden plants. Their root feeding is usually not enough to cause significant damage to healthy, well-established plants.

Moreover, cicadas are not known to transmit any diseases to plants, nor do they cause physical damage to plant tissues like some other sap-sucking insects, such as aphids or scale insects. The main issue with cicadas is often their sheer numbers, which can make them seem more problematic than they really are.

Foliar Feeding by Adult Cicadas

Once adult cicadas emerge from the ground, they feed on sap from the leaves and branches of plants. This feeding can sometimes cause yellowing or wilting of leaves, but it's usually not enough to seriously harm the plant. In fact, adult cicadas typically only live for a few weeks, during which time they are more concerned with mating than feeding.

Furthermore, adult cicadas are often more attracted to stressed or weakened plants. Therefore, if you're seeing a lot of cicada damage on your plants, it might be a sign that your plants are not as healthy as they could be. This could be due to factors like drought, nutrient deficiencies, or pest damage.

Cicadas and Plant Health: Myths and Facts

There are many myths surrounding cicadas and their impact on plant health. Let's separate fact from fiction:

1. **Myth: Cicadas kill trees.** While heavy infestations of cicadas can weaken trees, especially young or stressed ones, they do not typically kill healthy, mature trees. The damage caused by cicadas is usually minor and can be tolerated by most plants.

2. **Fact: Cicadas can be beneficial to some plants.** Some plants, like certain species of oaks and maples, are known to benefit from the presence of cicadas. This is because the holes made by cicadas in the plant tissues can stimulate the production of hormones that promote plant growth.

3. **Myth: Cicadas are a major agricultural pest.** While cicadas can cause some damage to crops, they are not considered a major agricultural pest. Most crops can tolerate the level of damage caused by cicadas and continue to produce a reasonable yield.

4. **Fact: Cicadas are an important part of the ecosystem.** Cicadas play a crucial role in the ecosystem, serving as a food source for many animals, including birds, bats, and even some insects. Their periodic mass emergence also provides a unique opportunity for scientists to study population dynamics and other ecological processes.

In the vast majority of cases, cicadas are more of a nuisance than a serious threat to garden plants. While they can cause some damage, especially to young or stressed plants, this damage is usually minor and can be tolerated by most plants. If you're concerned about cicadas in your garden, the best course of action is often to simply wait them out. They will eventually die off, and your plants will continue to grow and thrive.