Hey, my
name is Nick Voleski with USU’s Extension's Integrated Pest
Management Program, and I work as the vegetable IPM associate.
And my name is Zach Schumm, and I am the arthropod diagnostician
and urban Integrated Pest Management associate for Utah State University.
Extension.
So right now it's early July and we are at a community garden site in Logan, Utah.
And we're going to be looking for grasshoppers.
Grasshoppers are one of the most problematic
conspicuous insects that we have here in Utah.
They're a huge problem in our pastures are small grain crops
and even our home landscapes.
So in this video, Zach and I are going to talk about the biology,
how to monitor for them and what we can do to manage them.
so there are hundreds of species of grasshoppers in North America
and even more throughout the world.
Luckily, grasshoppers are very easy to identify.
They look like a large hopping insect.
And we know that it's a hopping insect because it has a very large
thickened femur,
which has a lot of musculature that they that aids them in jumping.
And then on the end of that, they have a tibia just like humans,
a femur that's very thick and larger, and then a tibia that's a little bit thinner.
So grasshoppers there are other insects that appear to be
like grasshoppers that you might confuse for grasshoppers.
What you can do is
you can look at the length of the femur in relation to the length of the abdomen.
So there are some other insects like katydids, that have very, very large
and elongate femurs that extend well beyond the length of the abdomen.
However, grasshoppers, the femur never extends past the length of the abdomen.
So that is how you can differentiate
between grasshoppers and some other large hopping insects that we can find in Utah.
There are three major groups of grasshoppers that we find in Utah.
The ones that are typically damaging
our crops and our plants, one are the spur throated grasshoppers.
These grasshoppers are large and robust on their sternum,
which is the underside of their thorax between the front legs.
There is a conspicuous spine present that is used to identify them.
The next to large group are the band wing
grasshoppers, their faces mostly vertical, facing up and down.
They don't have much curvature to their face,
but there is a lot of variation here.
Their wings always reach the tip of the abdomen as adults,
but many species have wings that extend far past the abdomen
when seen jumping and flying.
The hind wings are usually colored.
They can be different colors such as black, red or variations.
They also tend to make noise when in flight.
The third group are the slight face grasshoppers.
As the name would suggest.
These faces are very slanted and typically point front to back
where the mouth is pointing towards the back end of their body.
Otherwise, their features are quite variable.
There are over 400 species of grasshoppers found in the western states
of the United States.
Most of the grasshoppers that are major crop pests,
at least in Utah, are spur throated grasshoppers.
But other types of grasshoppers can feed on crops as well.
There are four species in particular that are very common in Utah.
The first one is the two striped grasshopper.
These can be major pests on small grains, alfalfa and corn.
It is an early emerging species with the eggs
hatching in early spring and adults appearing in the early summer.
Adults are easy to identify as they have two distinct yellow
stripes on their pronotem then and extending down the wings.
The second species of grasshopper that is a
major pest in Utah is the differential grasshopper.
This species feeds on weeds, grasses, fruits and vegetables.
So it has a very wide host range.
Eggs hatch in the late spring and adults emerge early to mid-summer
as they develop quickly after their late hatching period due to warmer conditions.
Overall, the species is yellow to tan, often with black markings
and has conspicuous black Chevron markings on the enlarged femur.
The third species that is a major crop pest
and plant pest in Utah is the red legged grasshopper.
These can feed on forbes meadows, crop borders and roadside plants.
Eggs hatch.
About three weeks
after the two stripe grasshopper, which again emerges in the early spring.
And adults of these are present in the late summer to mid fall.
Adults have a bright yellow
underside and characteristically have a bright red hind tibia.
The fourth species that is a major crop pest in Utah
and is also the most devastating species of grasshopper in the United States
is the migratory grasshopper.
The migratory grasshopper can feed on forbes, grasslands and meadows,
but is also the most destructive grasshopper in the US too
alfalfa, grains, clover, corn and other vegetables.
This species hatches in early spring and development
to adulthood can take as little as 35 days.
Swarming and mass movements can occur on any days above 80 degrees Fahrenheit.
Adults are fairly nondescript, but overall they are tanned to yellow with slightly
darker wings behind femur or dark brown with white or brown chevron markings.
Next, we're going to discuss the general life cycle of grasshoppers.
Most grasshoppers in Utah experience one generation per year, meaning
that there is one cycle from nymph to adult throughout one specific year.
These eggs are typically laid in the summer months
and and fall and the nymphs emerge the following spring.
As soon as these eggs are laid in the soil, they begin to develop.
Once winter hits, the development stops and then finishes in the following spring.
These eggs are laid in the soil in and nearby their appropriate habitats.
They are small ovular and can be laid in groups
or dispersed throughout the soil singly.
Nymphs.
Grasshoppers look just like adults,
except they are smaller and do not have fully formed wings.
There are usually five nymph stages before the grasshopper reaches adulthood.
As the nymph stages grow and as they molt.
You can typically see
winged buds start to develop, but nymphs never have fully formed wings.
Adults, however, do have fully formed wings.
So if you see a grasshopper that has wings that extend towards
to the abdomen tip or extending past the abdomen,
you are most likely looking at an adult grasshopper.
Otherwise, they look just like the nymph stages.
Adults are the only stage that are capable of reproducing
and also have a higher capacity for movement.
Although nymphs also in some cases have a high capacity for movement as well.
There are many climactic and weather conditions that impact
grasshopper population on a yearly basis.
The first thing to note is that really cold winters are very unlikely
to completely demolished grasshopper populations for the following year.
Eggs are very freeze tolerant, and with the additional snowpack
that we experience in Utah, it helps to insulate the eggs for the winter months.
So it's very unlikely that a very cold winter would kill a lot
of the grasshopper populations for the following year. In the spring.
Warm conditions and dry conditions can assist grasshopper populations
and help them explode or help outbreaks.
Cool and wet conditions.
Any time those are experienced in the landscape can help hamper
populations of grasshoppers and lower their numbers.
This is because cool and wet conditions can allow for their parasites,
their predators and fungal pathogens
to impact their populations and to survive and reproduce a little bit better.
If you have any questions
about identifying grasshoppers or questions about grasshopper behavior
or biology, feel free to contact the Utah Plant Pest Diagnostic Lab.
And if you guys have additional questions.
You can also contact your USU Extension County office near you.