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Showing posts from April, 2020

New publication on caterpillars now available

Cecropia is one of 15 caterpillars discussed in the new U of MN Extension site.     Photo:  Jeff Hahn, Univ. of Minnesota Extension Just in time for the growing season, new information about caterpillars is now available on the University of Minnesota Extension Insect web site. Entitled Caterpillars on ornamental plants , this page discusses how to identify caterpillars, their biology, the kind of injury they cause, and their management. There are 15 specific caterpillars described, divided into one of four categories: Non-web building caterpillars on trees and shrubs; Web building caterpillars on trees and shrubs; Large, showy caterpillars; and Caterpillars on perennials and annuals. Each of the 15 caterpillars is described in detail explaining how to recognize them, their favorite plants, their life history, and their feeding damage. This site is lavishly illustrated with 47 pictures to help identify the caterpillars and their feeding. Next time you need help with a

Safeguard yourself from ticks

An adult female blacklegged (deer) tick, a potential vector of Lyme disease and other diseases. Photo:  Jeff Hahn, UMN Extension As we enjoy spring, we seek outdoor activities to not only embrace the pleasant weather but to also help relieve some of the stress of being sequestered at home. Unfortunately with spring also comes ticks. Not to worry, with a few precautions, you can still enjoy the outdoors and protect yourself from these eight-legged pests. How to ID your tick The two most common ticks in Minnesota are the blacklegged tick (formerly called deer tick) and the American dog tick (also called wood tick). Both ticks are nuisances because they bite us for our blood. More scarily, they can also carry diseases which they can transmit to us. By far, the blacklegged (deer) tick is the most important disease carrier in Minnesota. This tick is responsible for giving us Lyme disease. From 2010 – 2018, there have been over 10,500 reported cases of Lyme disease in M

Don't fear centipedes

As gardeners return to their gardens this spring and start preparing it for summer’s plants, they unearth all kinds of insects and other arthropods. One arthropod people have been encountering has been soil centipedes. Because they don’t recognize them, people have questioned if they are pests. Unfamiliar Typical soil centipede.  Photo:  Whitney Cranshaw, Colorado State University, yes, but pests definitely not. You can recognize all centipedes from their flattened bodies, their long conspicuous antennae, and their 15 or more pairs of legs (interestingly it is always an odd number). There is just one pair of legs per body segment (compared to millipedes, which have two pairs of legs per body segment) and they are typically quick moving. In general, centipedes are found in moist areas, such as leaf litter and mulch and under objects such as stones and logs where they are predators mostly on small insects and other arthropods. Soil centipedes are common but

Troubleshooting seedling problems

Gardeners across Minnesota have been starting seedlings at home. While we hope your seedlings are healthy and vigorous, some of you are likely seeing some common problems such as seedling collapse, or tall, spindly plants. This guide is meant to help you troubleshoot issues. Not enough light Are your seedlings looking leggy? This is the term used for seedlings with very long, skinny stems. “Legginess” in seedlings is caused by low light, one of the most common problems when starting seeds at home. Eventually this will result in weak stems, and the plant will struggle to support itself. If you have a sunnier window, consider moving your plants there. Otherwise you may need to include artificial lights. If you have artificial lights already, try moving them closer to the plants. Too much water This is another common issue with seedlings grown at home. The seedlings in the photo below are tipping over from the top; a condition known as epinasty. When your soil is water-logged i

Yard to Table 101: Plant some cool season veggies now

Lettuce growing in a container on a patio table. Photo: Carol Reed I don’t know about you—but by the spring, I am hankering for my own fresh, homegrown vegetables!  That’s a summertime thing you say? As brief as spring can be in Minnesota and our region, you can still grow cool season crops with success.  In fact, you know how warm the sun feels right now?  You can take advantage of it—even warm the soil up to get seeds and transplants off to a good start—we’ll tell you how in a just a bit. This is Part 2 of our "Yard to Table" series of articles that will help you get growing—even if you’ve never planted seeds before!  You’ll find tips and resources here, and a place to ask your questions, too. That’s what we’re here for!  What are cool season crops?  When it comes to growing vegetables, these are crops that do well when the weather is still cool and spring-like, the soil is cool or sometimes will grow better when they’re partly shaded.  Many plants prefer certa

Smart Garden 2020: Armchair learning!

Crocus blooming in Mary Meyer's lawn--an early nectar and pollen source for pollinators. Photo: Mary Meyer, UMN Extension With our screen time now being ALL time, many people are looking for credible online gardening and horticulture resources. Here is a list of my favorites: UMN Extension videos Watch lots of informational videos on everything from seed starting to our 3-part series on how to pick the right place for the right plant . Tune into the University of Minnesota Extension's Yard and Garden YouTube channel ! Interested in learning more about growing fruit? Here are some of Extension's YouTube videos you might be interested in.  You can also check out our general UMN Extension videos . MN State Horticultural Society The Minnesota State Horticultural Society is one of the oldest horticulture societies in the U.S. Their Northern Gardening magazine is a great resource and this link provides a long list of information that is online. More benefits with m

Creepy But Harmless: Grape Aerial Roots

Aerial roots on a grapevine in eastern MN.  Photo: Annie Klodd. I receive about 12 calls, texts, and emails throughout the year from grape growers who have spotted an alarming and somewhat disconcerting anomaly on their grapevines. The question usually goes something like this: "Hello Annie, I have found these weird finger-looking things growing out of my vines. What are these? Are they a problem?" These long, skinny red structures, which grow from the trunks or limbs (cordons) of the vines are called grape aerial roots. Why is my vine producing grape aerial roots? Grape aerial roots, in themselves, are harmless. There is no evidence suggesting that they will impact the health or fruit production of the vine. However, grape aerial roots may actually be a sign from the vine that it is stressed or that it has experienced injury in the recent past. Eric Stafne, a horticulture professor at Mississippi State University, has written an eXtension article describing ae

Yellowjacket nests are empty now

A common question now is what should be done about any old wasp nests that survived from last year. The good news is not a thing! Whether the nests are hanging from a tree, in a wall void in your home, or in the ground, there are no live yellowjackets remaining in them. To understand why this is so, we need to look at yellowjacket biology If you have a wasp nest this spring, no worries. All of the yellowjackets died last fall.  Photo: Jeff Hahn, University of Minnesota Extension Yellowjackets have an annual life cycle; nests survive for just one season. At this time of year, the only yellowjackets from last season are new queens, which have spent the winter in protected sites, like under loose bark or cracks and spaces in a building. Once temperatures warm up in the spring, these queens become active and start searching for places to build their nests, typically somewhere quiet and protected. They feed themselves and forage for sources of wood, which they make into a p

Ask Extension: Will my apple trees cross-pollinate?

Spring flowers, Haralson apple Q: I know apple trees require two cultivars to cross pollinate and produce fruit. However, my trees haven't produced apples even though they have bloomed prolifically. Are my trees compatible for cross-pollinating? A: My friend, Jeanie in Montgomery, MN, is an avid, knowledgeable gardener with acres of land planted for bees. Haralson apple, a 1922 U of MN release She grows a selection of dwarf / semi-dwarf apple trees: Honeycrisp, Honeygold, Haralson, and Whitney crab. Her 4-year old trees have flowered very well the past two years, but haven't produced much in the way of fruit. She contacted me wondering about tree compatibility and their bloom time. I went to the best resource: our U of MN fruit breeder and apple expert, Dr. Jim Luby. Here's what he had to say about cross pollination of apple trees: I tell people not to worry about this in MN. We don't encounter issues in our breeding program as we do our p

Check out Small Wonders! Are you fascinated by flies, admire ants, love Lepidoptera (butterflies and moths), bonkers for bees or just generally like to learn about nature? Then the Department of Entomology may have a new column for you! Starting in February, the Department of Entomology unveiled a new feature named Small Wonders . This column helps to engage people that are interested in insects and related arthropods and attract those who don’t know yet they like entomology. These short articles entertain and educate and tell readers what’s cool about insects. New articles are published the first Monday of every month; columns are archived so you can read past articles. April currently features the mourning cloak butterfly .  You can find Small Wonders on the Department of Entomology home page as well as on social media: Twitter , Instagram , and Facebook . Check it out and enjoy! Author: Jeffrey Hahn, Extension Entomology

Minnesota WeatherTalk: A blog worth the read!

There are many great resources for Minnesotans here at the U of MN. One of my favorite weekly blogs is Minnesota WeatherTalk by climatologist Dr. Mark Seely and the following, fascinating excerpt from this week's post is why: April 2-3, 1982 All Four Seasons Were Sampled: Following one of the snowiest winter seasons in state history (over 90 inches in the Twin Cities), April 2, 1982 brought the first severe weather day of the spring season to western Minnesota. Many portions of southwestern Minnesota were under a severe thunderstorm watch that day. Bright sun, strong southerly winds, recent loss of snow cover, accelerated the daily temperature rise, producing afternoon highs in the 70s F. It reached 78°F at Lamberton, 77°F at Worthington, 75°F at Windom, and 68°F at St Peter, all readings about 15-20 degrees F above normal. Atmosphere instability brought by the clash of an air mass from the southwestern USA and an air mass which dropped down from Alberta, Canada caused huge bil

Emerald ash borer discovered in Mower County

After finding emerald ash borer (EAB) for the first time in Rice County two weeks ago, the Minnesota Department of Agriculture (MDA) announced yesterday that EAB is now confirmed in Mower County. An MDA employee, traveling on highway 63, sighted several suspicious trees with woodpecker pecks and bark splits near Racine,Minnesota. Upon further investigation Woodpecker pecks is a red flag for a potential EAB infestation.  Photo: Jeff Hahn, U of MN Ext. by MDA, live larvae were found which were confirmed later by federal identification. This is the 23nd county in Minnesota that has verified EAB. This discovery is not surprising as it is a mere five miles from Stewartville in Olmstead County, which found EAB in 2014. Minnesota first found EAB in 2009 and its nearly one billion trees are at risk from this invasive borer. EAB, first found in North American in 2002, has been confirmed in 35 states and 5 Canadian provinces. It has killed hundreds of millions of ash trees an

NEW VIDEOS: Seed starting inspiration from our systems at home

Seed trays of peppers and tomatoes. Photo: Julie Weisenhorn, UMN Extension Spring is in the air, and it's time to start your seeds! Many of us are starting to feel restless at home, and seed starting is a great way to get your hands dirty and feel connected to nature. (For those of you who are not stuck at home - healthcare workers, farmers, grocery store employees - thank you so much for your service!) To give you some inspiration, this video series shows three different seed starting systems at the homes of Extension educators. These systems highlight different options for starting seeds - from lighted, heated systems to sunny windows, and materials ranging from specially created seed starting pots to objects found around the home.  Your access to materials is likely limited during the COVID-19 closings, so don't be afraid to get creative! A few things to keep in mind: 1. If you have a really great seed starting system, consider growing extra for your neighbor

Yard-to-Table 101: Take your first steps to 'Homegrown' veggies!

As history has shown…when times get tough, Americans often turn to gardening—because of scary, fresh food supply shortages and for health reasons. When World War II began in September of 1939, who knew that by 1943, 40 percent of Americans would be gardening in their own “Victory Gardens”?  Thanks to the pandemic, you might want to garden because you’re stuck at home, you’d like to try your hand at something new, or you really want your own homegrown fresh produce—it’s healthy, tastes good, and it’s good for the environment—all positives that we need right now.  At UMN Extension, we can help you with this new yard-to-table journey!  This is the first in a four-part series on easy vegetable gardening that will give you the tools to create your own vegetable garden.  Never gardened before? No problem! Got just a patio or an apartment balcony? No worries!  Lettuce grown in a pot on a patio/balcony. Photo: Carol Reed We'll show you how to do something as simple as growing

Big Ideas for Small Spaces: Succession planting

Good candidate vegetables for succession planting. Photo: Natalie Hoidal Even in a small space, you can harvest vegetables all season long with some up-front planning. Succession planting is the practice of seeding crops at intervals of (usually) 7-21 days in order to maintain a consistent supply of harvestable produce throughout the season.  Succession planting also involves planting a new crop after harvesting the first crop. The second crop (or third!) can be the same as the prior, or different. Make a plan for fresh vegetables all summer long In a small space, I tend to stick to quick-growing crops like lettuce and radishes, or crops that can grow vertically on a trellis like peas. Rather than planting all of my peas and radishes at once, I calculate the amount that I'm likely to eat in a week.  For example, I will likely only eat 5-7 radishes each week. So, rather than planting all of my radishes at once, I'll plant a ~10 radish seeds one week, 10 the next wee