Kellogg's tarweed

Kellogg's tarweed (lat. Deinandra kelloggii) is an annual herbaceous plant belonging to the Asteraceae family. In agronomy, it is identified as a problematic weed that can thrive in various agricultural settings, potentially causing economic losses if left unmanaged within crop fields and grazing lands.

The biology of this plant is characterized by a taproot system and a branched, glandular-hairy stem that exudes a sticky resin, which is a common trait of the tarweed genus. This plant is well-adapted to Mediterranean-type climates, capable of completing its life cycle during dry periods. It reproduces via a high volume of seeds that remain viable in the soil for extended periods, contributing to long-term infestation problems.

It is primarily found in Western North America, particularly in regions where it invades cereal crops, oilseeds, and perennial pastures. The weed's competitive nature allows it to aggressively utilize soil moisture and nitrogen, often resulting in stunted growth for the surrounding crops and reduced overall field yields.

The damage caused by Kellogg's tarweed is twofold: direct competition for resources during the vegetative growth phase and negative impact on harvesting efficiency. The dense, resinous biomass can clog harvesting machinery, slow down operations, and increase the moisture content of the harvested crop, complicating drying and storage processes.

Effective management requires an integrated weed management (IWM) program involving the following strategies:

• Implementing diverse crop rotations to disrupt the weed life cycle.
• Mechanical cultivation prior to crop emergence to destroy seedlings.
• Targeted use of systemic or contact herbicides approved for the specific crop variety.
• Maintaining healthy crop density to provide natural shading that inhibits tarweed germination.