Issue no. 8 of the Home, Yard & Garden Newsletter


Guignardia Leaf Blotch

Guignardia leaf blotch is a fungal disease that affects many Aesculus species.  In Illinois, this disease is commonly seen on the common horsechestnut (Aesculus  hippocastanum).  Symptoms begin as rapidly enlarging, irregularly shaped,  water-soaked areas.

Modified Growing Degree Days (Base 50°F,  March 1 through May 15)

Insect  development is temperature dependent. We can use degree days to help predict insect emergence and activity. Home, Yard, and Garden readers  can use the links in this article along with the degree day accumulations to determine  what insect pests could be active in their area.

Illinois  Invasive Plant Phenology Report

Several invasive plant experts  from around the state have started a new series of reports focusing on the  phenology of invasive plants in Illinois. The intent of these reports is to  provide an update on the development of invasive plants across the state of  Illinois — what plants are in bloom, leafing out, setting seed, or senescing in  different areas of the state.

Thousand  Cankers Disease Confirmed in Indiana, Fungus Found on Insect Other than Walnut  Twig Beetle

The Indiana Department of  Natural Resource issued a press release on Friday, June 20 announcing the  detection of Thousand Cankers Disease in Indiana. Indiana joins Maryland, North  Carolina, Ohio, Pennsylvania, Tennessee, Virginia, and eight western states  with the disease.

Palmer Amaranth — A New Weed to Watch For

Ask any cotton farmer what has been their biggest weed  problem of recent years and they will all likely tell you the same:  Palmer amaranth (Amaranthus palmeri).  This  plant has put some southern farmers out of business. Midwest farmers are now or  will soon be well acquainted with this fast growing and yield robbing species  as it is moving northward across the Midwest.

Japanese Beetle

Japanese  beetle adults are present throughout Illinois. Robert Bellm, Extension  Educator, reported their presence in Madison County, and Ed Nangle, Chicago District  Golf Association, reported their presence in Cook County. Last week in this  newsletter, we predicted low numbers in the northern half of the state due to  the extended deep soil freezing last winter.

Fall Webworm

Fall  webworm is named for infestations that occur in the northern part of the United  States only in late summer to early fall. In the southern half of the United  States, including the southern half of Illinois, fall webworm has an additional  generation in early summer. This first generation of fall webworm is now  feeding in southern Illinois.