Green June Beetle
The Cotinis nitida or Green June Beetle (also known simply as the June beetle) is a member of the Scarabaeidae family. This beetle is found throughout the entire United States on a large scale. They are often confused with the Japanese beetle. In reality, the Japanese beetle is about a half-inch smaller than the Green June Beetle. They are primarily active during the daytime.
Cotinis nitida is a serious pest, particularly renowned for attacking fruit crops. It causes severe loss in the yield of fruits, attacking the fruit plants during their mature ripened stage. Soil with a lot of organic or decomposed matter is great for the growth and development of Cotinis nitida. The beetle emerges from the soil during the rainy season in July or August. There are several irregular stripes running throughout their elytra and exoskeleton. The colors of these spots may vary from orange-yellow, to dark brown, to black.
Taxonomy and classification
Cotinis nitida is an important member of the Scarabaeidae family inside the Coleoptera order (also known as the order of the beetles). The suborder for this beetle is Polyphaga. Members of the Polyphaga suborder also include long-horned, leaf, and snout beetles. The genus Cotinis contains several other species in addition to the June Beetle. Two species hailing from this genus are significant pests. They are:
Apart from these two pests, C. polita, C.producta, C. antonii, etc are the most relevant species in this genus. The entire genus was first described by German entomologist Herman Burmeister in 1842.
Availability, Distribution, and Habitat
The Green June Beetle is found in almost all parts of the world, except places with extreme environmental and/or weather conditions. They can be noticed flying around through the entire summer season. Green June Beetles are commonly found in agricultural lands, woods, or on lawns. These beetles are found throughout the U.S. in large numbers, especially in the eastern and southern parts.
The Figeater Beetle is commonly found in southern parts of the USA. Parts of California and Texas are the major hotspots for their development. Figeater Beetles have extended from the state of Georgia to many corners of the world. Temperate conditions with mild humidity are ideal for the growth of the Green June Beetle.
Adult Green June Beetles are green in color, with orange or rusty stripes at the outer margin of their metallic wing covers. Their body size is usually between a half inch and an inch. During the larval stage, grubs can grow up to 1.6 inches in length. The grubs are generally white in color. They are found in large numbers in soil rich in organic matter. These beetles take flight during the night. They form a C shape when disturbed. The color of this insect varies from green, to brown, to black.
The pupal stage of Green June Beetles is active for 2 to 3 weeks in April and May. Generally, they remain in the soil up to the month of August. June and July are the preferred months for the beetle to take flight. Males and females take flight early and late in the morning respectively. There is an attractant in the substance secreted by the female which attracts the male for mating. The females choose a location for laying the eggs after mating. Usually, soil with high organic matter is selected for laying eggs. Soil with rich organic matter or decomposed matter is a rich source of June beetle larvae. The larvae grow under the soil.
The females lay about 10 to 30 eggs is a walnut-shaped ball made from soil particles. The eggs are round, measuring 1/16th of an inch in diameter. The eggs take about 2 weeks to hatch, under favorable conditions. The measurement of a grub is usually about 3/8 inch in length. Tunnels are formed by these groups, beneficial in the case of low grub-counts. An increasing population of grubs can cause harmful effects. The Green June Beetle takes one year to complete a generation cycle.
The larvae of Sarcophaga aldrichi (the large flesh fly) is a parasitic predator of the Green June Beetle. Attached to the thorax region of the adult Green June Beetle, this fly leads to the death of the beetle due to impairment of the respiratory system. Sarcophaga helicobia can lead to the death at the larval as well as the adult stage of the Green June Beetle. Another remarkable predator that feeds on the larvae of the Cotinis nitida beetle larvae (that are placed under the soil) is the digger wasp, Scolia dubia. It is a wasp specialized in digging holes into the ground and finding prey.
Apart from the wasps and flies, several vertebrates feed on this beetle. Skunks, chipmunks, and birds predate on the beetle larvae when they crawl over the ground surface. This occurs especially in the rainy season because their holes are filled with water and the larvae feel suffocated. Blue jays, common grackles, mockingbirds, and the common crow are examples of some birds that feed on the larvae of Green June Beetle, as well as the adults.
A Proper Agricultural Pest
The June beetles primarily attack a large number of fruits such as grapes, peaches, raspberries, strawberries, apricots, and many more. They attack these fruit crops in the rainy season, causing severe damage to ripened fruits. Before attacking fruits the larvae feed on dead organic matter or FYM in the soil.
Management of Green June Beetle
Bacillus popilliae is a popular option to control the larval stage of Green June Beetles effectively. Bacillus popilliae is the causal organism of milky disease. This method was originally used by American farmers to control the Japanese beetle. The effect of this biological control option can be as long-lasting as 10 years, after successful implementation. The control period is affected by environmental conditions like humidity, temperature, sunshine, the velocity of air, etc.