Skip to main content

Posts

Showing posts from July, 2014

Managing Cherry Disease Problems

M. Grabowski, UMN Extension
Photo 1:


Michelle Grabowski, UMN Extension Educator

Several disease problems have been observed on cherry trees this summer including powdery mildew and brown rot. When disease problems arise in the garden it is critical to identify what pathogen is causing the problem. There are different strategies to manage each disease and it is important to know what time of year management strategies should be applied. Many garden diseases can be significantly reduced if not eliminated with well timed cultural control strategies.

Find out more about identification and proper management of disease and insect problems of cherry, plum and apricot trees in the new UMN Extension publication Pest Management for the Home Stone Fruit Orchard.

Watch for Masked Hunters

Jeffrey Hahn, Extension Entomologist



Jeff Hahn, Univ of Minnesota Extension
Photo 1: Masked hunter adult - they can bite if you are not careful

Some people have been encountering a 3/4 inch long, dark colored, somewhat slender insect in their homes lately. This insect is a masked hunter, Reduvius personatus, a type of assassin bug (family Reduviidae). A masked hunter is a predator, feeding on a variety of insects. It can accidentally wander into homes during summer and is considered to be just a nuisance invader. No more than a few are usually seen at a time.

Fortunately, a masked hunter is not aggressive towards people, although it is capable of inflicting a painful bite if it feels threatened. It also is not a carrier of any disease. This is important as a masked hunter has been confused with kissing bugs which do transmit Chagas disease. Chagas disease is a potentially serious illness caused by a protozoan organism.

Kissing bugs also belong to the assassin bug family which h…

Hollyhock Rust at its Worst

M. Grabowski, UMN Extension
Photo 1: Hollyhock rust on leaves

Michelle Grabowski, UMN Extension Educator


Frequent rains this spring and early summer have created favorable conditions for hollyhock rust. Hollyhock rust is caused by the fungal pathogen Puccinia malvacearum, which infects hollyhocks and related weeds like roundleaf mallow (Malva neglecta).

Early symptoms of hollyhock rust are easily missed. Small waxy yellow bumps form on the lower surface of the lower leaves of the plant. With age, these pustules turn reddish brown and a bright orange spot develops on the upper leaf surface. In wet years, spores from these early infections easily spread to infect leaves, stems, petioles and even flower bracts. Heavily infected leaves turn yellow and may wither and curl. This significantly reduces the plant's ability to do photosynthesis. The hollyhock rust fungi can survive from one season to the next in infected live crowns, as spores in infected plant debris, or on seed from infecte…

Diseases in the Vegetable Garden

Michelle Grabowski, UMN Extension Educator

M. Grabowski, UMN Extension
Photo 1: Black rot is a bacterial disease of broccoli, cabbage, cauliflower and other brassicas.


This years frequent rains have created ideal conditions for many fungal and bacterial diseases in the vegetable garden. These pathogens need moisture to reproduce, spread and start new infections. Although gardeners can't change the weather, a few things can be done help plants dry out after rain or dew and to reduce the spread of disease.

1. Space plants to allow for air movement around the plants and through the foliage. Dense planting results in fruit and foliage that stay wet longer; a favorable condition for many pathogens.

2. Pull weeds. Weeds crowd the vegetable plant, steal nutrients and reduce air movement in the garden.

3. Completely mulch the soil with landscape fabric, plastic mulch, straw or wood chips. Many pathogens survive in plant debris and soil. Rain and irrigation splash water, soil and …

Join a CSA (Community Supported Agriculture) and visit that Farm!

Karl Foord, Extension Educator - Horticulture




Karl Foord
Photo 1: Some of the plastic tunnels that provide optimum growing conditions on the Untiedt Vegetable Farm



Karl Foord
Photo 2: Sweet corn on Untiedt Farm



Karl Foord
Photo 3: Trellised tomatoes on the Untiedt Farm



Karl Foord
Photo 4: More trellised tomatoes on the Untiedt Farm



Karl Foord
Photo 5: Trellised cucumbers on the Untiedt Farm



Karl Foord
Photo 6: Trellised cantaloupe on the Untiedt Farm



Karl Foord
Photo 7: Onions on Untiedt Farm



Karl Foord
Photo 8: Honeybee hives on the Untiedt Farm



Karl Foord
Photo 9: Protective tree barriers on Untiedt Farm

If you are not already a member of a CSA (Community Supported Agriculture), I highly recommend that you consider becoming one. To be a member one pays an up front fee and receives weekly a box of currently maturing vegetables for 17 weeks of the season. This prepayment helps the farmer to achieve better cash flow for the operation and the member/shareholder gets a greater understa…

Apple Maggots Foiled Again!

Karl Foord, Extension Educator - Horticulture



Karl Foord
Photo 1: Apples showing maggot damage next to protected apple



Karl Foord
Photo 2: Larger apple maggot trapped in nylon guard after exiting apple



Karl Foord
Photo 3: Apple maggot enters apple through flower end and leaves frass



Karl Foord
Photo 4: Small apple cut to reveal resident maggot



Karl Foord
Photo 5: enlarged view of apple maggot resident in small apple

The nylon apple maggot barriers are doing a pretty good job in protecting the apples from the attack by maggots (Photo 1). One fly did manage to oviposit her egg through the nylon mesh. The apple was ruined but at least the maggot was trapped in the barrier sock (Photo 2). Many of the unprotected apples were attacked at the flower end of the fruit (Photo 3). One of these fruits has been cut open to reveal the small apple maggot seen in the lower right half of the right hand slice (Photo 4). Photo 5 is a close up of the same slice. It is obviously critical to get these …

Pseudoscorpions are Curious, Harmless

Jeffrey Hahn, Extension Entomologist

Bunni Olson, Univ. of MN Extension
Photo 1: Pseudoscorpions look fierce but are harmless to people
A small, 1/5th inch long, reddish or brownish 'bug' with two large 'pinchers' is sometimes found in homes. Although it looks like a tick or scorpion, it is actually a pseudoscorpion. A pseudoscorpion is not an insect but is a type of arachnid, so it is related to spiders, ticks, and true scorpions. Pseudoscorpions have eight legs and pincher-like pedipalps (part of their mouthparts). They lack the stinger that true scorpions possess.

Pseudoscorpions are predators on a variety of small insects and other arthropods, like springtails, booklice, and mites. They are found in a variety of habitats, such as leaf litter, moss, and under stones and tree bark, and occasionally buildings. Despite their appearance, they are harmless to people. If you find a pseudoscorpion in your home, just physically remove it or ignore it. If possible, capture …

Gypsy Moth Quarantine in Minnesota

Jeffrey Hahn, Extension Entomologist

(The following has been slightly modified from a June 30, 2014 news release from the Minnesota Department of Agriculture (MDA).

Bill McNee, Wisconsin Dept of Natural Resources
Photo 1: Lake and Cook counties are now under quarantine for gypsy moth



Due to the high number of gypsy moths trapped in northeast Minnesota in 2013, the Minnesota Department of Agriculture (MDA) has placed Lake and Cook counties under quarantine effective July 1, 2014.This is the first time a quarantine for gypsy moth has been established in Minnesota. A quarantine helps to prevent gypsy moths from being moved by human activity to uninfested counties.

Outdoor items in the quarantined counties, like logs and firewood, camping equipment and patio furniture, that could be infested with gypsy moth must be inspected and certified as gypsy moth-free before moving to a non-quarantined area. This is done in two ways:

Homeowners, campers and others who live in and visit the propos…

Repairing Lawns Following Flooding

The month of June was a wet one. Many homeowners, grounds managers, and golf course superintendents are finally starting to see some of the flood waters recede, although standing water is still covering many of our landscapes. The University of Minnesota's Climatology Working Group is calling June of 2014 the wettest month on record. In the Twin Cities we saw 11.36 inches of rain for the month, almost 7 inches above average and falling just short of the 11.67 inch record set in 1874.

We are starting to see a wide range of damage to lawns and turfgrass throughout the state. In situations where standing water was present for greater than 7-10 days, the turf is almost certainly dead and will need to be repaired. Turfgrass covered for less time has a greater chance of recovery, but every situation is different. Unfortunately, there is not good information regarding how long turfgrass can survive under standing water because there are so many potential mechanisms of damage. The…

Beauty is in the Eye of the Beholder

Karl Foord, Extension Educator - Horticulture



Karl Foord
Photo 1: Native bee nesting site on U of MN St. Paul campus



Karl Foord
Photo 2: Native bee leaving nest to forage - nest hole lower right of photo



Karl Foord
Photo 3: Native bee nesting site on Como Ave. St. Paul



Karl Foord
Photo 4: Native bee navigating grass in front of nesting site



Karl Foord
Photo 5: Native bee approaching nest with pollen load



Karl Foord
Photo 6: Native bee nesting site - Purgatory Park, Minnetonka



Karl Foord
Photo 7: Native bees at hole entrances



Karl Foord
Photo 8: Bauer Berry Farm - Champlin, MN; Note each flag represents a single nest



Karl Foord
Photo 9: Nest entrance hole Bauer Berry Farm - Champlin, MN

One of the projects I am engaged in this summer is the identification and location of the nests of native bees. My partner in this effort is Heather Holm, who is the author of a recently published book entitled, "Pollinators of Native Plants". With additional help from Joel Gardner, a bee b…

Japanese Beetles Have Arrived

Jeffrey Hahn, Extension Entomologist

Japanese beetles have started showing up in gardens; the first discoveries of them were made in late June. It does not appear the late spring slowed down their emergence too much as the first week of July is about when we expect to see these beetles. It will be interesting to see how abundant they are this year. Because they were well insulated under the snow, it is not expected that last winter's cold weather had much effect on their populations.

However, a factor that does impact their relative numbers is the soil moisture at the time eggs are laid. The eggs and young white grubs are particularly susceptible to dry soil conditions. Eggs are laid soon after adults start to emerge, generally early to mid-July. However, older grubs are much more tolerant of dry soil. So the number of Japanese beetles that are present this year is related to soil moisture last summer. Although we have experienced drought in many recent years, 2013 was a f…