Blog2020-03-22T18:50:45+00:00

The official blog of the Oregon State University Plant Clinic

Brown rot – an aptly named and unwelcome disease of stone fruits

I have a sour cherry tree in my yard that declines a bit more each year. It is in sad shape, with seared-open main branches injured by sun scald and invaded by decay fungi. This all stemmed from leaf loss due to an ongoing and pervasive case of brown rot caused by the fungus Monilinia. This organism infects first through the flowers, usually after a rain while the flowers are open.

April 21st, 2020|Categories: Plant disease|

Tea Scale: An unwanted hitch-hiker

Sunny days and warmer weather bring about thoughts of gardening: which plants are not performing as well as would be liked, which new ones would look better in that spot. If you are contemplating adding to your garden, be sure not to add an unwanted component: insect or mite pests (or disease) that might be tagging along with your new acquisition.

April 13th, 2020|Categories: Scales|

Pest and Weather Models

The Oregon Statewide Integrated Pest Management (IPM) Center has a great collection of online resources to support both commercial growers and home gardeners across the country. Their web-based tools include weather and climate driven models for IPM/pest models, plant disease risk models, crop models, horticultural models, beneficial species models, climate suitability models, and many others.

March 22nd, 2020|Categories: Online resources, technology|

The spotted lanternfly makes its first west coast appearance

Last September we published our first post about the potential for the spotted lanternfly, Lycorma delicatula, to be a pest of serious concern to Oregon agriculture. At the time, only a handful of eastern states had reported established populations (Pennsylvania has been the most impacted). More recently, a live adult spotted lanternfly was reported in Davis, California.

March 3rd, 2020|Categories: Emerging Pests|

Secretary of War brings back the flower of peace

The association of poinsettias with Christmas is said to have begun over 500 years ago. The plant has been growing in dry tropical forests, along the Pacific coast from Mexico to Guatemala, for even longer than that. In its native form, it grows as a lanky, long-stemmed small tree or large bush. The wild plant has brilliant red “flowers”, but the red bits are narrow, less eye-catching, and scarcely like those on the plants we see in garden centers.

December 17th, 2019|Categories: Uncategorized|

Garlic Gone Bad

Winter is the time to use your summer-grown garlic. Fortunately, we have great garlic-growing weather here in Western Oregon, although occasionally problems do arise. This week we are showing some common problems that can pop up and which are usually only found when you are cracking those heads, seeking the perfect cloves for your favorite potato and garlic soup.

November 26th, 2019|Categories: Garlic|

Calling all naturalists!

Our fun Friday feature is a short introduction to a really cool app called iNaturalist. iNaturalist is essentially an online social network of enthusiastic naturalists, citizen scientists, students, researchers and experts who provide a worldwide crowdsourcing species identification system. Record your own observations, get help identifying species you record, and join projects that can use your observations for research or education efforts. Take your smart phone into your backyard or out on a hike, and try recording your first observation.

November 22nd, 2019|Categories: technology|

Propagation pitfall: Leafy gall disease

Now is the time when nurseries are propagating plants for the upcoming spring season. Odd looking plants with too many shoots or buds could be infected with the pathogenic bacterium Rhodococcus fascians. Propagators should be alert for symptoms, as shown in the gallery below, and have suspicious plants tested for the presence of the bacteria.

November 12th, 2019|Categories: Leafy gall, Plant disease|

Botrytis on hemp… it’s in the news!

The weather this fall has been ideal for development of molds (like Botrytis) in the tight colas of the hemp plant. The alternating cool and moist weather followed by a few clear days of moderate temperatures have been perfect for the moisture-loving fungus. Which translates to bad news for the growers, who depend on the flowers for their CBD-related products.

October 8th, 2019|Categories: Botrytis, Hemp|