Archive for December, 2011

Sarah J. Vanek, University of Kentucky Extension Associate for Nursery Crop Production

Importance to the Nursery Industry

Maple shoot borer, Proteoterus aesculana (Riley) (Lepidoptera: Tortricidae), also known by the common names maple tip moth and maple twig borer, is a key insect pest of young maple trees in nurseries. Larvae cause tip dieback and flagging by tunneling into young growing shoots. Researchers at the University of Kentucky found that in some fields of newly transplanted Acer rubrum bare-root liners, as many as 100% of the trees were infested and 22–36% suffered flagging in the terminal leader (Seagraves et al, 2008). Destruction of the terminal leader causes undesirable forking and requires establishment of a new central leader. This increases labor costs and leaves an unattractive crook in the tree even when performed successfully.

For the entire publication, please visit:

http://www.ca.uky.edu/entomology/entfacts/ef455.asp

Sarah J. Vanek, University of Kentucky Horticulture Department

Consider for a moment the major advancements in global trade that have developed in recent centuries. International shipments that once took months or even years to transport now reach their destination within hours or days. With regular use of airplanes, semi-trucks, trains, and giant freighters, and with major changes in global-trade policies, the world continually transports massive amounts of cargo around the globe every day.

With these shipments come living organisms that discreetly ride commodities, packaging materials, trucks, ships, and numerous other pathways before entering a foreign habitat. In the past century, countless alien species entered the United States, many of which have caused severe economic and environmental damage. Harmful non-native species are extremely diverse. They include, but are not limited to, insect pests such as Japanese beetle, emerald ash borer, or gypsy moth; weeds such as garlic mustard or spotted knapweed; and plant pathogens causing diseases such as sudden oak death or chestnut blight.

The level of economic or environmental damage sometimes caused by non-native organisms is alarming. Therefore, it is critical that individuals transporting plant materials as well as state and federal agencies that regulate these shipments remain diligent in preventing movement of harmful pests. Here is a basic explanation of some of the regulations that may apply to nursery businesses’ shipping activities.

For the complete publication, please visit:

Plant Material Shipments: Federal and State Plant Protection Regulations Relevant to Your Nursery Business
PDF: 568 kb, 4 pages

Nicole Ward and Don Hershman, University of Kentucky Department of Plant Pathology

Win Dunwell, University of Kentucky Department of Horticulture

Soybean cyst nematode (SCN) is the most serious disease pest of soybean in the United States and results in an estimated $1 billion in losses annually. SCN is a microscopic roundworm (Heterodera glycines) that feeds on root of soybean and reduces its capacity to absorb water and nutrients. Yield losses of 30% or more are common where SCN-susceptible soybean varieties are grown and SCN levels are high. SCN was first discovered in Kentucky in 1957 in Fulton County but is now found in every Kentucky county in which soybean is grown commercially.

SCN causes a problem for field production nurseries because Canada and some states—for example, California— do not allow soils (in ball-andburlapped materials) to be imported without proof that the nursery stock comes from SCN-free counties. Other states, including Pennsylvania and New York, assume that the blanket statement “free from all pests” includes SCN. SCN survives in soil as long-lived cysts (Figure 1). The cysts can be spread by any means that spreads soil particles, including windblown soil; soil attached to roots of host or non-host plants; soil peds in bird droppings, seed bags, or stock feed; flood water; or farm and construction equipment.

Essentially anything that causes soil to be moved from one place to another can spread SCN cysts into previously un-infested soil. Quarantine restrictions are an attempt to limit the continued spread of the nematode or more aggressive types of SCN in places like Ontario, Canada, that already have an SCN problem.

To learn more – check out the following website:

Soybean Cyst Nematode: A Potential Problem for Nursuries
PDF: 368 kb, 4 pages