The Packard’s grasshopper (M. packardii) typically occurs throughout the prairies, preferring loose, sandy soils. There is some colour variability in this species within Alberta, with southern specimens being generally paler. This species is less common than two-striped grasshopper and is a more moderate threat. Population numbers can increase in areas with sandy soils and dry conditions.
For general grasshopper information, see Overview.
Figure 1. Adult Packard's grasshopper settling in on an alfalfa plant
The adult grasshoppers are grey to dark yellow and approximately 27 to 32 mm (1.1 to 1.3 inches) long. Two light-coloured stripes extend from just behind the eyes to the posterior margin of the thorax. The forewings are uniformly grey and lack distinctive stripes. The last 2 segments of the hind legs are blue-green. When newly hatched, Packard’s grasshoppers are pale green to yellow-brown and are speckled with numerous small dark spots (Figure 2).
The young Packard’s grasshoppers have scattered black dots on their bodies and look much like they walked under a pepper shaker.
Figure 2. A fourth instar Packard’s grasshopper (M. packardii). Note the green wingpads.
The Packard’s grasshopper prefers light, textured soils with scanty grass cover, and is similar in other respects to the migratory grasshopper.
Most Packard's grasshoppers can eat from 30 to 100 mg of dry weight material per day. They readily feed on broadleaf crops like pulses and alfalfa, and on cereals and grasses.
Host plants and damage
Because Packard's grasshopper prefers herbs to grasses, it causes little damage to range land but will damage field and garden crops and legume pastures. It feeds on leaves, stems and flowers of many plants. Cereals and alfalfa are heavily attacked.
Females lay one to several egg pods in grain fields or along roadsides, mostly in August and September. Each pod contains about 20 eggs. The egg stage overwinters.
Eggs hatch between early May and mid-July, depending upon temperature and moisture conditions. Nymphs, which are green or fawn coloured, molt through 5 nymphal instars before becoming adult in 2 to 7 weeks. In cooler seasons, development is slowed and nymphs persist into the fall.
Number of generations
As with all of Alberta's grasshopper pests, Packard’s grasshopper has one generation per year.
Late summer and fall surveys of grasshopper adults have been carried out by Agriculture Fieldmen in Alberta since 1932. Grasshopper population maps are produced yearly from data collected in about 1,700 townships.
Spring surveys of grasshoppers and grasshopper eggs are also conducted in years when high grasshopper numbers are expected. In this way, improved estimates are obtained for time of hatch, population density, and the effects of predators and parasites.
Next to weather, natural enemies are the grasshopper's most important population control factor. In some localized areas, natural enemies may cause even more mortality than the weather. Find out about predators, parasites, pathogens and other grasshopper natural enemies.
Packard's grasshopper occurs in the 4 western provinces. It is the second most important species of grasshopper in Alberta, and the third most important in Saskatchewan where it has comprised 12% of the total grasshopper population. It tends to be associated with the migratory grasshopper and occurs especially in stubble fields and in light soil areas. Packard's grasshopper has caused considerable damage to fall rye and winter wheat.
For more information, see Grasshopper – Economic thresholds.