As you eagerly await the bountiful harvest from your spring and summer garden, remember that pests are also eyeing your crops. Scouting for pests is essential to maintain plant health and ensure a plentiful harvest.
The Importance of Scouting
Scouting involves the early detection of pests and plant diseases through regular and systematic garden inspections. This proactive approach helps identify pests early and assess the damage they might be causing. Missing just a few days of scouting can lead to significant plant damage due to the rapid life cycle of many plant-eating insects.
Understanding Your Garden Environment
To effectively scout for pests, familiarize yourself with the plants in your garden and their common pest issues. Different plants attract different pests, so knowing what to look for is crucial. Monitor your garden regularly, at least once a week, paying close attention to the undersides of leaves, stems, and flowers. Look for any leaf discoloration, such as yellowing or browning, and any unusual color changes. Note any insect activity, including the presence of eggs, holes in leaves, skeletonized foliage, insect frass (droppings), and entry holes.
Photo: UF/IFAS
Tools Frequently Used in Scouting
Frequently inspecting your garden with the appropriate tools allows you to spot issues early and take steps to safeguard your plants. Common tools include:
Traps: Used to catch and identify flying insects.
Netting/Lures (Pheromones): Attract and capture specific pests.
Sweep Net: Collect insects from plants.
Containers: Collect samples to transport specimens for further examination.
Hand Lens: For close inspection of small insects and eggs.
Common Garden Pests
Here are some common garden pests you might encounter while tending to your garden:
Aphids: Small, soft-bodied insects that can be green, black, yellow, or brown. Often found on new growth, they cause curling and yellowing leaves and excrete sticky honeydew.
Caterpillars (e.g., Tomato Hornworm): Large, green caterpillars with white stripes and a horn-like tail. They create holes in leaves, remove foliage, and damage fruits.
Spider Mites: Tiny red or brown mites often found in clusters, creating fine webbing. They cause stippling on leaves, bronzing, and leaf drop.
Whiteflies: Small, white, moth-like insects that fly up when plants are disturbed. They cause yellowing leaves, stunted growth, and secrete honeydew.
Japanese Beetles: Metallic green bodies with bronze wings. They skeletonize leaves and damage flowers.
Cutworms: Fat, brown, or gray larvae found curled under the soil surface. They cut off young seedlings at the base.
Slugs and Snails: Soft-bodied, slimy creatures found in damp, shaded areas. They leave a trail of slime and create irregular holes in leaves and seedlings.
Scouting Techniques
Effective scouting techniques include:
Visual Inspection: Check plants thoroughly, including the undersides of leaves and leaf axils.
Sticky Traps: Place yellow sticky traps around the garden to catch flying insects like whiteflies and aphids.
Shaking Plants: Gently shake plants over a white piece of paper to dislodge and spot tiny pests like spider mites.
Soil Examination: Dig around the base of plants to look for soil-dwelling pests like cutworms.
Maintain a garden journal noting the types of pests observed, population levels, and control measures taken. Track the success of different pest management strategies to refine your approach in future seasons.
By consistently monitoring your garden and employing a combination of these strategies, you can effectively manage pests and enjoy a healthy, thriving garden throughout the spring and summer seasons. For more information, contact your local extension office. Happy gardening!
Migratory animals are no stranger to our neck of the woods. Every year, Florida is host to countless creatures as they make their way from one place to another in search of food, nesting sites, or just a change of scene. From hummingbirds to manatees, it can be interesting to watch the annual cycle of nomadic animals.
One of the smaller wayfarers we see year-round, but especially when they migrate south in the fall, is the gulf frittilary butterfly, Agraulis vanillae Linnaeus. They spend the warmer months of the year in the southeastern United States, following frost-free weather as temperatures drop. During the winter, they enjoy the sunshine of peninsular Florida.
The gulf frittilary is a medium-sized butterfly, with a wingspan of 2½–3½ inches. Females are larger than males. It is bright orange in color, with black markings on the top of its wings and silvery-white spots on the bottoms. In its larval form, it is also bright orange in color, with dangerous-looking spines along the length of the caterpillar. Despite their appearance, these do not sting.
If given a choice its larvae will feed primarily on passionflower (Passiflora incarnataand related species), but have also been seen snacking on buttonsage. Toxins from passionflower concentrate in the larvae and butterflies, making them poisonous to predators – much like the monarch butterfly and its host plant, milkweed. The insect’s bright coloration serves as a warning that it is not to be eaten.
Keep an eye out for these beautiful butterflies and consider planting a passion vine in your landscape to help them out. The caterpillars may eat the leaves, but in giving them a feast you’ll help them grow into adult butterflies. Once they do mature, they are fantastic at pollinating many of our native wildflowers, further beautifying the world around them.
For more information see the University of Florida’s article here.
Throughout the year, people with citrus trees of any sort may notice some damage to the leaves. Chewing damage, which leaves pieces of the leaf missing, is a common sight. The likely culprit for this type of damage is an insect that is very common in our area, but seems to have multiple personalities!
The adult form of this peculiar creature is the giant swallowtail butterfly, Papilio cresphontes Cramer. A large black-and-yellow butterfly, it is found throughout the country east of the Rocky Mountains, and is present in north Florida most months of the year. Adults spend their days as many other butterflies do, flitting from flower to flower in search of nectar. They are attracted to a wide variety of blossoms, pollinating as they go.
The giant swallowtail butterfly. Photo courtesy of Donald Hall, University of Florida
Females lay tiny round eggs individually on the surface of plant leaves. Though their larvae may eat numerous types of leaves, one of their favorites seems to be those of citrus trees. This means that though the adults may be considered beneficial as pollinators, their caterpillars are often thought of as pests.
Bird poop or caterpillar? The orange dog caterpillar is, in fact, a caterpillar.
Similarly, the beauty of the adult butterfly is quite different than the appearance of their younger selves. The caterpillar of the giant swallowtail, often called the ‘orange dog’ caterpillar, relies on camouflage to keep itself safe. Even with this it displays multiple personalities, so to speak. Larvae of any age may be mistaken as bird droppings on a leaf. Their irregular patches of white and brown make them look like the leavings of a passing avian, which predators are probably likely to pass over. Older caterpillars have another trick up their sleeve, with markings on their head that mimic the head of a snake. Disturb one enough and it may even flash a forked, bright orange protuberance called the osmeterium, which may resemble the tongue of a snake. This gland also emits a musky odor to make the insect even less attractive to potential predators.
Snake or caterpillar? The osmeterium might look like a snake’s tongue, but don’t be fooled. Photo courtesy of Donald Hall, University of Florida
Whether wearing a beautiful, ugly, or scary face, these insects are here to stay. Thankfully, they don’t often do enough damage to citrus trees for homeowners to worry about. Young trees in danger of being defoliated may need some protection, but an established tree can lose a leaf or three with no issues.
If control is called for, hand-picking the caterpillars is a viable option, as long as the tree is small enough to reach the branches. A product called Bt, short for Bacillus thuringiensis, is another option. Applied to the leaves, this insecticide only affects caterpillars, and shouldn’t harm other pollinators.
October is an important month for butterflies. The monarchs are making their epic migration towards Mexico, gracing us with their presence as they stop to feed on saltbush or lantana plants along the coast. But our homegrown orange-and-black butterfly is showing up everywhere right now, too. The Gulf fritillary (Agrautis vanillae) is a smaller species, but also features bright orange wings with black stripes and spots. Their caterpillars come dressed for Halloween, too—they are a deep orange color with black legs and spikes. While the caterpillar is not venomous to any potential predators, the spikes are quite intimidating and serve a protective function.
Fritillary (name from the Latin “chessboard”) eggs are bright yellow and laid primarily on varieties of passionflower vines, which the caterpillars feed voraciously upon. Passion vine is an important host plant for the zebra longwing as well, which is Florida’s state butterfly.
Gulf fritillaries are found in all 67 Florida counties, and may live throughout the southeastern United States, Mexico, and central and south America. They are found in varied habitats but prefer open, sunny spots in fields, forests, and gardens. The butterfly’s wing shape puts them into the “longwing” category, as their elongated wings spread wider than other species.
In the fall, fritillaries migrate to the warmest ends of their range. By spring, they move slightly north into North Carolina or interior Alabama.
A number of landowners in our region have been noticing a number of caterpillars coming down from the treetops. Sometimes appearing in vast numbers, the forest tent caterpillar has been found throughout Florida and the United States. Several years of heavy infestation occurred in Central Florida more than a decade ago, but populations are usually not high enough to cause significant damage to trees.
A forest tent caterpillar. – Photo courtesy of Shoal Sanctuary Nature Preserve.
The forest tent caterpillar is the larval stage of a somewhat nondescript brown moth. The moths lay their egg masses on twigs, and the eggs hatch in the spring. Caterpillars feed on a variety of tree species, but seem to prefer oak and gum trees. They spend anywhere from two to six weeks eating. When they are nearing maturity, they can become a problem for humans who do not appreciate the many droppings they produce, or their habit of descending from the trees to find places to spin their cocoons. They are sometimes attracted to lights or the walls of buildings, where they congregate in search of a place to pupate. They are not harmful to people, however.
A forest tent caterpillar egg mass. – Photo courtesy of Jeffrey Lotz, Division of Plant Industry
Particularly cold winters may help decrease populations of these caterpillars. Inclement weather or high temperatures may do the same in the summer, and natural predators often help to control populations when present as well. Controlling forest tent caterpillars is most often unnecessary even when there are large numbers of them. It may help to avoid parking cars under large infestations or to turn off outdoor lighting that might attract them at night. If they wander indoors, check screens and window seals to be sure there are no gaps for them to enter.
If these or other caterpillars become such a nuisance that control measures must be considered, consider using a product such as Bacillus thuringiensis, or Bt, which specifically affects caterpillars and not other beneficial insects. Keep affected trees healthy with proper fertilization and watering, and even a defoliated tree will probably recover from any damage these insects cause. For more information, see our EDIS publication on the Forest Tent Caterpillar or contact your local Extension office.