Field Crops Surveys
Illinois is the #1 producer of soybeans and #2 producer of corn in the nation. Marketing of Illinois agricultural commodities generates over $51.1 billion annually, with crops accounting for 40% of that total. Illinois ranks third nationally in the export of agricultural commodities with $8.2 billion worth of goods shipped to other countries. Exports from Illinois account for 6 percent of all U.S. agricultural exports. Illinois is the nation’s second leading exporter of both soybeans and feed grains and related products. Approximately 44 percent of grain produced in Illinois is sold for export.
Historically, Illinois corn and soybean production have suffered significant injury, yield reduction, and damage costing billions of dollars due to insect pests such as the western corn rootworm, European corn borer, Japanese beetle, and soybean aphids. Of additional concern are a number of pests that, while not yet widely established or present in Illinois, represent a potential threat not only to corn, soybeans, and several other agricultural commodities. Old World bollworm was first detected in the continental U.S. in 2015, and its morphology and capacity for significant damage to feed on field corn and sweet corn are nearly identical to that of its native congener, corn earworm. Furthermore, both species are increasingly resistant to pyrethroid insecticides. Silver Y moth is not known to occur in the U.S., but risk maps indicate that Illinois’ climate and host range could readily facilitate its establishment. The cucurbit beetle poses a risk to crops already infested with western corn rootworm, particularly in conjunction with rising levels of pest resistance to genetically modified corn seed. We continue to monitor brown marmorated stink bug populations in Illinois in response to worrisome yield loss estimates in several crops from the Mid-Atlantic region. Similarly, soybean loss estimates in the southern U.S. due to kudzu bug indicates a need for awareness of this pest in Illinois.
Agricultural pathogens are also of concern; recent confirmations of tar sport of corn and bacterial leaf streak in the state confirm the dynamic and ever-changing landscape of crop disease. Late wilt of corn, Philippine downy mildew, and Java downy mildew also remain on our radar and will be included in visual survey efforts. Clearly, the monitoring and/or early detection of these pests would have a substantial impact on agricultural production not only in Illinois, but across the Midwest.
Pathway Survey for Pests of Multiple Agricultural Pests
Of the 360 nonnative insect species that have become established in the United States, approximately 30% have become major pests impacting natural areas, community landscapes, agricultural interests, and green industry. Of additional concern are nonnative species not currently known to occur in the U.S., but at risk of introduction via international trade. The goal of this program is to monitor high-risk pathways in Illinois for defoliators of the flighted spongy moth (FSM) complex (Lymantriidae: Lymantria spp.), Old World bollworm (OWB | Noctuidae: Helicoverpa armigera), and spotted lanternfly (SLF | Fulgoridae: Lycorma delicatula).
Repeated U.S. port interceptions of species within the FSM complex (L. dispar asiatica, L. dispar japonica, L. mathura, L. monacha, and L. umbrosa) demonstrate the ability of these species to enter the U.S. via trade. Lymantriid moths deposit egg masses on flat surfaces such as cargo containers or stationary vehicles; their spread and establishment to new areas benefit significantly from anthropogenic movement. The seven-county Chicago metropolitan is a major hub for the movement of goods throughout the U.S., with approximately 25% of all freight trains and 50% of all intermodal trains in the U.S. passing through Chicago. Additionally, the Chicago Metropolitan Agency for Planning (CMAP) forecasts that regional truck volume will surpass 1.2 billion tons by 2040 – a 71% increase from 2007 levels. These factors, when combined with Illinois’ temperate climate and suitable host tree density, could readily facilitate the establishment and spread of these nonnative moth species throughout the state as well as the greater region.
These taxa are significant defoliators and pose a risk to Illinois’ forest product industry and nursery trade. According to the Illinois Forestry Development Council, solid wood and solid wood processing contribute an estimated $2.59 billion to the Illinois economy, while the logging industry adds an additional $122 million. Furthermore, the Illinois Green Industry (including nurseries, landscape contractors, and garden centers) supplies $5.2 billion to the Illinois economy. Undoubtedly, tree health and nonnative forest pests are of concern to Illinois.
Another invasive threat commonly intercepted at U.S. ports of entry, OWB is considered one of the most damaging agricultural pests worldwide due to its broad host list, migratory ability, rapid reproductive capacity, hybridization with native congeners, and ability to develop resistance to various insecticides. OWB is native to Africa, Asia, Australasia, and Europe, but was reported from South America in 2013 and the U.S. territory of Puerto Rico in 2015. In the continental U.S., repeated detections of OWB around Chicago O’Hare International Airport (ORD) since 2019 indicate the presence of a small reproducing population capable of overwintering in the area. Although the exact source of introduction is unknown, over two million metric tons of cargo volume from 25+ international carriers transit ORD each year, a significant proportion of which are risky commodities such as cut flowers, fresh herbs, and produce.
CAPS-funded field crop surveys have not detected OWB anywhere else in Illinois or the continental U.S., and ongoing APHIS PPQ monitoring suggests that the established ORD population is likely small and highly localized. That said, the potential for this pest to negatively impact U.S. agriculture and trade cannot be underestimated; even considering only the most climatically optimal locations, modeling by Kriticos et al (2015) suggests that $843 million worth of U.S. crops would be at risk should OWB become widely established in North America.
The same pathways ideal for movement of FSM are also excellent corridors for the spread of SLF, whose egg masses can travel long distances attached to vehicles, trailers, outdoor equipment, scrap metal, and building materials. Of particular concern is the movement of these articles from infested areas; as the extent of the SLF infestation in the eastern US expands, it will not only physically encroach on Illinois but also rapidly increase the volume and rate at which infested material enters or transits the state – the entirety of which is considered to be at high or medium risk of SLF establishment.
In September 2023, SLF was first detected in Cook County, Illinois. Continued early detection of SLF in Illinois could potentially increase the chances of successful eradication or management, mitigate the associated financial burden, and protect growers, green industry, and agri-tourism interests throughout the state.