Which species are present and whether mosquitoes are an annoyance or vectors for diseases likely depends on those conditions? Similarly, the temperature, availability of water and type of water available, such as clear floodwater in ditches, a wheelbarrow that has collected water or stagnant puddles in hot, dry weather are all contributing factors to what type of mosquito is visiting you and your family.
The annual mosquito boom
Rainfall, especially with multiple storm systems that have saturated and flooded areas around the state, can significantly contribute to a boom in mosquito populations.
People are seeing, and should expect to see, quite a bit more mosquito activity in the next days and weeks. Our focus is going to be disease carriers that typically become a problem in late summer and early fall. However, all this rain has created plenty of habitat for floodwater and container species.
Mosquitoes come in waves and can overlap as the season progresses.
First wave: floodwater mosquitoes
Floodwater mosquitoes are the first to emerge after rain events.
Heavy rains leave the ground saturated and create standing puddles in ditches and low spots in fields and lawns. Floodwater mosquito larvae emerge quickly after water becomes available. Eggs are placed there by females and wait for water, sometimes two to five years before rainfall reaches them depending on the species.
Floodwater mosquitoes are typically larger and are aggressive. These types of mosquitos are often the persistent biters from dawn to dusk.
Any location that is holding water, even in grassy areas, could be a breeding ground.
Second wave: container mosquitoes
Container mosquitoes, which include the Aedes species identified by its black and white body and white striped legs, typically emerge next. Female mosquitoes lay eggs in anything holding water – from tires, buckets and wheelbarrows to gutters, unkept pools and trash cans. They prefer clearer, fresher water, and females are constantly looking for good breeding sites.
Container mosquitoes like Aedes are daytime feeders but can be opportunistic at nighttime when large groups of people gather.
Any time after a rain, it is good to make a round on the property to look for anything that might be holding water. It just takes a matter of days for these mosquitoes to go from egg to biter, so they can become a problem pretty quickly.
Third wave: Culex mosquitoes
Culex, a mosquito species that prefers stagnant pools of water with high bacteria content, typically emerge as waters recede and dry summer conditions set in and create breeding sites in low-lying areas. They are the disease carriers that concern the public and health officials.
In rural areas, bogs, pooled creek beds or standing water in large containers such as barrels, trash cans or wheelbarrows can make a good habitat for Culex.
How to repel mosquitoes from yourself, children, and pets
Reducing mosquito numbers in your location and the use of spray repellents are a good start when it comes to protecting yourself from bites. Covering exposed skin with long-sleeved shirts and long pants help as well.
Plants like citronella, geraniums, lemongrass, lavender, lantana, rosemary and petunias have been shown to repel mosquitoes, the distribution limits effectiveness for protecting a space.
Candles and other smoke-based repellents fall into a similar category as plants.
Protecting yourself with any spray-on, CDC-approved repellent like DEET, picaridin or lemon eucalyptus oil is my best recommendation anytime you go outside for an extended period,” she said. Personal protectants are the only certainty against bites.
Pets should be removed from areas with mosquito infestations. Small children should not be taken outdoors for long periods if mosquitoes are an issue because they can have adverse reactions to mosquito bites, and spray products should be used sparingly on them, especially babies. There are age restrictions for most repellents; no repellents on babies less than 2 months old and do not use lemon of eucalyptus oil on children 3 and under.
This time of year, it’s just best to limit their exposure to mosquitoes.
How to control, prevent mosquitoes
Controlling mosquitos after widespread, heavy rains is difficult because their habitat can be so unpredictable, Swiger said. Container mosquitoes are a bit easier – remove the habitat by dumping the water or treat the water with granular or dunk larvicides.
Sprays or barrier treatments that kill adult mosquitoes are another option, but effectiveness is limited, Swiger said. Products that homeowners can apply only last 24 hours.
Grasshoppers and Their Control
Grasshoppers are among the most widespread and damaging pests in Texas. There are about 150 species of grasshoppers in the state, but 90 percent of the damage to crops, gardens, trees and shrubs is caused by just five species.
Differential grasshopper, Melanoplus differentialis
Black chevron markings on the hind femur help identify this species. Adults are 11⁄8 to 13⁄4 inches long. They move into fields from weedy borders and can be very destructive to crops. They are seldom found in grassland.
Red-legged grasshopper, Melanoplus femurrubrum Adults are 7⁄8 to 11⁄4 inches long with red hind tibia. This species is especially damaging to alfalfa and other legumes, but they can be a problem in other crops, too. They are not a problem in grassland.
Migratory grasshopper, Melanoplus sanguinipes This species is very destructive to both grasslands and cultivated crops. Adults are 7⁄8 to 11⁄8 inches long. These grasshoppers are strong fliers and may swarm over long distances.
Two-striped grasshopper, Melanoplus bivitattus Adults are 1 ¾ inches long with two light stripes that extend from the eyes to the wing tips. They eat mostly weeds but will also move into cultivated crops.
Packard grasshopper, Melanoplus packardii This species prefers sandy soils with light grass cover. They are the least damaging of the five species, but large numbers of them can be a problem in both grassland and cultivated crops.
A sixth species is not as damaging. It is the:
Lubber grasshopper, Brachystola magna The lubber grasshopper prefers weedy areas but can be a problem in crops also, especially cotton. It is seldom a problem in grasslands. Adults are 1 ¾ to 2 inches long. These grasshoppers are flightless and their limited mobility makes them less damaging than the top five species. Lubber grasshoppers will feed on dead insects, even their own kind, in certain situations.
Grasshoppers cause some damage every year, but they become very destructive during outbreaks. The main factor affecting grasshopper populations is weather. Outbreaks, or exceptionally large populations, are usually preceded by several years of hot, dry summers and warm autumns. Dry weather increases the survival of nymphs and adults. Warm autumns allow grasshoppers more time to feed and lay eggs. Grasshoppers have a high reproductive capacity. The female lays an average of 200 eggs per season, and sometimes as many as 400 eggs. If favorable weather increases the number of eggs, nymphs and adults that survive, the grasshopper population may be dramatically larger the following year.
Grasshoppers deposit their eggs 1⁄2 to 2 inches below the soil surface in pod-like structures.
Grasshoppers have many natural enemies that help control their populations. A fungus, Entomophthora grylli, often kills many grasshoppers when the weather is warm and humid. Infected grasshoppers strike a characteristic pose at the top of a plant or other object. The grasshopper grasps the plant in a death embrace with the front and middle legs, while the hind legs are extended. It dies in this position. Fungal spores develop in and on the grasshopper’s body, then become airborne and infect other grasshoppers.
Other natural enemies include nematodes called hairworms and insects that feed on grasshoppers, such as the larvae of blister beetles, bee flies, robber flies, ground beetles, flesh flies and tangle-veined flies. Birds (quail, turkey, larks, etc.) and mammals also eat grasshoppers, but have little effect on large populations.
One way to control grasshopper populations is to eliminate sites where they might deposit eggs. Grasshoppers prefer undisturbed areas for egg laying, so tilling cropland in mid- to late summer discourages females. Tilling may reduce soil moisture and contribute to erosion, but those disadvantages must be weighed against potential grasshopper damage to the next crop.
Farmers and ranchers should start watching for grasshoppers early in the season and begin control measures while grasshoppers are still nymphs and still within the hatching sites (roadsides, fencerows, etc.). Treating grasshoppers early means 1) having to treat fewer acres and use less insecticide, 2) killing grasshoppers before they cause extensive crop damage, and 3) killing grasshoppers before they can fly, migrate and lay eggs. Also, smaller grasshoppers are more susceptible to insecticides than larger ones.
You can estimate the size of a grasshopper infestation by surveying for nymphs or adults with the “square foot method.” Count the number of grasshoppers that hop or move within a square foot area. Then take 15 to 20 paces and sample another square foot area. Make 18 samples in all.
a.) Fruit, nut, citrus, stone fruit, pome fruit and shade trees. Consult specific pesticide labels prior to use.
b.) Includes Conservation Reserve Program acres, set-aside acreage, wasteland, rights-of-way and ditch banks.
c.) Labeled for control of specific pests (grasshoppers) in multiple sites. Refer to individual site listings for use limitations and restrictions. Refer to Rangeland Use Directions for the Reduced Area Agent Treatments (RAATs) program should such a provision exist for the specific product chosen.