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On Farm Food Safety Workshop

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By Jake Overgaard
Extension Educator, Winona County

We've seen the headlines linking spinach, sprouts, melons, or what-have-you with an e. coli outbreak. The impact of an outbreak on an individual farm and the industry in general is significant. Also, with the recent Food Safety Modernization Act (FSMA) legislation, and more scrutiny from buyers and the public, addressing food safety risks on the farm is becoming more important. This is especially true as more local producers are selling to co-ops, restaurants, grocery stores, farmers markets, and through CSAs. As a grower you might be wondering...

  • When would I need a certification to sell fresh produce?
  • How will FSMA affect my operation?
  • How can I create a food safety plan for my farm?

To address these questions and provide more information regarding on-farm food safety, the UMN On-Farm GAPs Program http://safety.cfans.umn.edu/ and UMN Extension - Winona County, have put together a workshop for commercial produce growers. At this workshop, you will...

  • Learn about GAPs, GAP Certification, and FSMA.
  • See how Whitewater Gardens implements GAPs on their farm
  • Practice writing risk assessment statements and standard operating procedures.
  • Learn about additional resources available to you.

Location: Whitewater Gardens, Altura, MN
Date/Time: June 26th, 9 am to 4 pm
Cost: $15 (Includes lunch and refreshments)

For more info and to register, visit the registration page: https://docs.google.com/a/umn.edu/forms/d/1Y0dhZWbmr2WH9sUx8Q4CjyBsQzM6JIfMiwaDtuMXCPY/viewform

We hope to see you there!

Fall Soil Testing is a Good Investment

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By: Jerrold Tesmer, University of Minnesota Extension in Fillmore & Houston Counties

Soil testing, in any type of agricultural or horticultural landscape, can provide a number of benefits. A soil analysis takes the guesswork out of fertilizer recommendations, makes good economic sense and ensures fertile soil without excess fertilizer application. Based on the results of the University of Minnesota Soil Testing Laboratory, the local Extension office can provide area residents with their specific soil conditions, and ultimately offer more accurate advice and consultation to their questions.

Soil testing kits, which include sample bags, collection recommendations and a soil sample information sheet, are available at both the Fillmore and Houston County Extension Offices. Instructions for sampling soil in both small and large landscapes are also offered. After the sample has been collected and mailed to the University of Minnesota Soil Testing Laboratory, located on the University of Minnesota's St. Paul Campus, the results are processed within three to five days and returned to the landowner.

Along with the returned soil test results, recommendations are provided for nutrient application. Please contact me in Caledonia or Preston, at either Extension office, if assistance is needed to interpret the recommendations or soil test results.

More information regarding soil testing through the University of Minnesota can be found at http://soiltest.cfans.umn.edu or http://www.extension.umn.edu/nutrient-management/
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Fertilizer recommendations in Minnesota are based on "Fertilizer Guidelines for Agronomic Crops in Minnesota" BU-06240-S Revised 2011, Daniel E. Kaiser, Extension Soil Scientist; John A. Lamb, Extension Soil Scientist; and Roger Elieason, Director, University of Minnesota Soil Testing Laboratory.

Spring Planting and Care of Trees

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By: Nathan Winter, Extension Educator, McLeod & Meeker Counties

Trees are often enjoyed more by people that come after those that planted the tree. Trees help define how a yard in the city will look and the type of landscaping that can be done by determining shade or full sun types of plants. Businesses and city municipalities also use trees to help make areas more astatically pleasing to those that are working within in those areas as well as those that are using those areas for recreation. In rural country settings, trees serve many purposes, but one of the core purposes is protection from the weather elements.

We need to know when and how to plant trees to get them started off in the right direction. According to the University of Minnesota Forest Resource Extension, in the Midwest region, bareroot trees and shrubs should be planted when the plants are dormant in the spring or at the end of the growing season (fall). Balled and burlapped, containerized, and container grown plants can be planted throughout the growing season, but with caution during the summer months. If planting in the fall, the recommendation is to plant four weeks before the soil temperature drops below 40 degrees Fahrenheit. To plant trees correctly, obtain a copy of the U of M publication called "Planting and Transplanting Trees and Shrubs", which can be found at http://z.umn.edu/e8m.

Watering is going to be important to a newly planted tree as well as any existing trees on your landscape. Since watering is such a time consuming task, you may have to pick and choose the existing trees that you want to water. I recommend watering any newly planted trees and also water any trees that have shown stress, disease, or insect problems through the growing season.

Water newly watered trees over the root zone of the tree. Established trees should be watered around the "root zone" of the tree. Roots of trees can vary from 1.5 to 3 times as wide as the canopy. Avoid frequent light watering and instead water infrequently and heavy. You will want to wet the soil to a 6 - 8 inch depth and then let the soil dry out in between. Use a rod to determine when you have wet the soil to that depth. Believe it or not, you can over water trees, which will starve the roots of oxygen and cause roots to rot. If rains are averaging one inch every week, watering will probably not be necessary.

Protect stems of landscape and shrub trees from animals and mechanical equipment. This is most important on new or young shrubs and trees. Use a mesh or hardwire cloth at least three inches from the stem. Plastic guards can also be used, but they are only recommended to encase the lower part of the stem, where damage can take place. Sun scald can be prevented by wrapping the trunk with a commercial tree wrap, plastic tree guards, or any other light-colored material. Put the wrap on in the fall and remove it in the spring after the last frost. Wraps should be used primarily on new trees.

Fertilizing trees should be done on a case by case basis. A soil test can be done to determine if the soil does not have the adequate amounts of fertilizer in the soil. U of M Soil Test Kits can be picked up at most U of M Extension Offices or by contacting the U of M Soil Testing Laboratory: http://soiltest.cfans.umn.edu/. Often, the tree has sufficient amounts of nutrients available if the lawn is already being fertilized regularly. To learn more about fertilizing trees, obtain a copy of the U of M publication called "Tree Fertilization: A Guide for Fertilizing New and Established Trees in the Landscape", which can be found at http://z.umn.edu/e8n.

Do the best you can to educate yourself on caring for those beloved trees properly. Proper care will help increase the longevity of your landscape trees and give you and others years of enjoyment and admiration for the trees.

Still Time to Prune Trees

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By Nathan Winter
Extension Educator, McLeod and Meeker Counties

The spring time weather will soon be heading our way with April only weeks away. The winter period has been the time for meetings and the spring brings outdoor activities and scratching of the soil for planting. From recent phone calls in the McLeod and Meeker County Extension Offices, I can tell people in the community are thinking ahead to spring. They are wondering what they should plant and how soon they can start? Often, many of the common questions revolve around tree management. For example, when should I prune my apple trees? Well, if you have not already, there is still some time for certain species of trees.

Prune apple trees, including flowering crabapples, mountain ash, hawthorns and shrub cotoneasters in late winter from February to early April. Spring or summer pruning increases chances for infection and spread of the bacterial disease fireblight. Autumn or early winter pruning is more likely to result in drying and die-back at pruning sites. Oaks, ash, and elm trees can also be pruned this time of year.
Pruning approaches include crown thinning, crown raising, and crown reduction. Crown thinning is primarily used in hardwoods to increase the amount of room for light and air to penetrate the tree. You still will want to maintain the trees natural shape, and form.

Another form of crown thinning is to make sure there is only one dominant leader instead of two or more co-dominate leaders on the tree. Crown raising is cutting off some of the bottom branches to permit travel underneath the tree. This could be for lawn mowers, people, and vehicles. Be sure not to raise the crown of the tree too high to avoid an excessively high crown.

Crown reduction is another approach to pruning. This method should be used only in a last resort when the tree has outgrown its permitted space. This approach should not be used on trees with a pyramidal growth form.

Topping and tipping pruning practices do more harm to trees than they help. Topping is pruning large upright branches between the nodes and is sometimes done to reduce the height of the tree. Tipping is pruning lateral branches between nodes to reduce the crown width. These practices result in sprouts and dead branches that will reduce the life of the tree. Use the crown reduction method as a last resort and avoid topping and tipping.

What about treating the wounds? Most of the time the tree sap, gums, and resins naturally work to decrease pathogens invading the trees. Therefore, there are very few circumstances when wound dressings are needed for pruning cuts. Often, they create more problems than they avoid.

The University of Minnesota Extension Website contains a vast amount of information. The website has further information pertaining to pruning other types of trees. Following is a great link to learn more about pruning trees and shrubs: http://www.extension.umn.edu/distribution/horticulture/dg0628.html.

By: Julie Sievert, Extension Educator, Sibley County
Christian Lilienthal, Extension Educator, Nicollet County
Mike Donnelly, Extension Educator, Rice & Steele Counties

Do you have the dream of owning acreage in the country? Do you have an existing acreage that is in need of a plan and strategies for the best possible results? The Living on the Land Workshop Series, offered by University of Minnesota Extension, will equip you with the education and resources to be successful.

The eight-week course is designed to arm landowners with agricultural information to enable them to be good stewards of their land. The course will begin with goal-setting and individual property inventory, then address soil, plant, water and animal basics.

The Living on the Land curriculum addresses a growing need for information regarding small acreages. The series incorporates knowledge and experience from a team of instructors to address topics including: what do you have and what do you want, what you can do with your land, protecting water quality, what to do about weeds, lawn and pasture maintenance, getting down and dirty with soils, and caring for and managing your animals. The series also includes a farm tour.

The series will be taught by Extension educators and natural resource professionals at two locations. One of the locations is in Gaylord at the Sibley County Service Center. In Gaylord, the series will be held on Monday evenings from February 4th to March 25th. The second location is in Northfield at the Northfield Community Resource Center. In Northfield, the series will be held on Thursday evenings from March 7th to April 25th. Both workshops will run from 6:00 p.m. to 9:00 p.m. with light meals provided at each session.

Early registration is $175 until Monday, January 28 for the Gaylord location and Thursday, February 28 for the Northfield location. All registrations received after those dates will be $200. Each registration is valid for up to two people representing a single farm who will share materials. For example, a husband and wife team or two siblings may attend together. Benefits include useful educational publications, an educational farm tour, soil tests, a site visit/consultation from a University of Minnesota Extension educator in your area, as well as the tools to help you succeed with your goals and dreams on your country acreage.

For more information about the series in Gaylord, please contact Julie Sievert at 507-237-4100 or schu0944@umn.edu or Christian Lilienthal at 507-934-0360 or lili0004@umn.edu. For questions regarding the Northfield location, please contact Mike Donnelly at 507-332-6109 or donne099@umn.edu.

Register now--space is limited at each location. Additional information and the Living on the Land workshop series brochure can be found on the Small Farms website.

Ag Business Management Websites

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By Jerrold Tesmer
Extension Educator, Fillmore & Houston Counties

While preparing for the recent Land Rent Workshops, I stumbled across a list of useful Ag Business Management websites that Regional Extension Educator Gary Hachfeld and I prepared many years ago. I checked out those sites to see if they were still working and added a couple that are useful. Anyone with internet access might find them useful. These sites are in no particular priority.

A great place to start is the University of Minnesota Center for Farm Financial Management: www.cffm.umn.edu. At that site you can access FINBIN data. FINBIN is the largest and most accessible source of farm financial and production benchmark information in the world.

Other useful items under the Center for Farm Financial Management site include, The Ag Risk Education Library that organizes thousands of risk management materials which help producers and agricultural professionals quickly locate information, tools, and assistance on specific risk management topics; AgTransitions helps farmers and ranchers develop a plan to transition their business to the next generation; Grain Marketing where Ed Usset attempts to separate the wheat from the chaff in the often confusing world of grain marketing.

Value of Farm Land: Land Economics Web site at www.landeconomics.umn.edu. This is a site is prepared by Steve Taff, University of Minnesota. Over the years, I have shared it with a number of realtors. The site includes Farmland sales, Timberland sales, Land values, soils data, RIM easements, CRP contracts, and Property tax assessments.

I have also found three very useful publications from Iowa State University, "2012 Iowa Farm Custom Rate Survey", "Estimated Costs of Crop Production in Iowa - 2012", and the "Livestock Enterprise Budgets for Iowa - 2012". They can be accessed at: www.extension.iastate.edu/agdm.

The final source I will mention is the National Agricultural Statistics Service (NASS). USDA, NASS has a wealth of data at www.nass.usda.gov or strictly Minnesota data at www.nass.usda.gov/mn/.

Raspberry Pruning

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By Jake Overgaard
Extension Educator, Winona County

Pruning of raspberries is done to improve yield, ease of management/harvest, and to lower the incidence of disease by removing dead/dying tissue, increasing light penetration/air movement, and spray penetration. Below are some simple guidelines for pruning different types of raspberries. Remember that raspberries have perennial roots and biennial canes. The canes are distinguished as primocanes (1st year's growth) and floricanes (2nd year's growth).

Primocane Fruiting Raspberries aka Everbearing

  • Prune floricanes to the ground after final harvest

  • Thin primocanes (next year's floricane) late in the fall to 4-5 per linear foot (If concerned about hardiness, thin in the spring when winter survival is apparent)

  • Head back (prune) floricanes in spring just below winter injury point, or no more than 25% the height of the cane
Summer-Bearing Red & Yellow Raspberries

There are two options for primocane fruiting raspberries; they can be pruned to produce a summer and fall harvest, or a fall harvest alone. Pruning for fall berries alone is much easier, but there is more risk that you won't get a crop because of fall frost risk and because there is no summer crop.

If you want both summer and fall berries...


  • Thin the primocanes (next year's floricane) to 4-5 canes per linear foot, select the best canes

  • If concerned about hardiness, thin in the springtime when winter survival is apparent

  • In the spring, prune the floricane a few inches below the last node that produced fruit as a primocane in the fall

If you want only fall berries...


  • Cut all canes down to the ground in the Spring before growth starts. Yep, that's it


Black & Purple Raspberries

  • Tip the primocanes (cut or pinch off the top 2-3") when they reach 24-30"

  • Prune side branches to 12-18" on floricanes in the spring and select 4-5/hill

  • After fruiting, cut floricanes to the ground
  • For more information on raspberry production, visit Raspberries for the Home Garden at http://z.umn.edu/83u.

Thinning Apple Trees - Less is More?

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By Jake Overgaard
Extension Educator, Winona County

I know it's exciting in the spring when apple trees are flowering and the trees are covered in blossoms. We naturally want to preserve every single flower and hope that it becomes a perfect apple that we pick and eat straight off the tree. The thought of going out and deliberately removing tiny apples before they really even have a chance is unthinkable to some, but you should think about it.

Thinning fruit can have multiple benefits. First, if you want your trees to produce consistently each year, thinning (and being timely about it) can have real benefits. Thinning can help minimize what is called "biennial bearing", or when a tree produces lots of apples one season and few to none the next. Biennial bearing is especially common in Honeycrisp and Haralson cultivars, among others. Also, by having fewer apples on a tree, fruit size improves and the apples can mature more evenly as well. Trees have limited energy, so fewer apples means there are fewer "mouths to feed". Also, on younger trees and weaker branches, fewer apples can prevent branches from breaking.

So when should you thin apples? First of all, wait until "June drop" has passed (I'll let you guess when that usually occurs). June drop is when a tree naturally sheds some of its fruit, leaving you with fewer apples to thin yourself. Depending on the year, June 20th or so is about the time to start thinning, but a simple rule of thumb is to thin when the apples have the diameter of a dime. Thinning at this time will help to prevent biennial bearing and help maintain the future year's yield. Even if you don't get started at exactly the right time, the current year's production will benefit from your efforts.

Thin apples down to one fruit per cluster (typically there are 5 per cluster) and leave 6 inches in between each apple or roughly a fist length. Also, using this standard will help you determine if you need to thin; the tree may already have a light crop due to frost or other effects, in that case, don't thin. It is possible to thin by hand, simply remove the fruit from the stem. However, you want to be sure that you aren't damaging the tree by tearing off any spurs. A small pruner or even a scissors works pretty well. At first, it may seem like a daunting task, but with a little practice, you can become a speedy thinner. I know some growers who feel terrible when they have to thin (be it an apple, a carrot, or a radish for that matter), but less is more in this case, and your final product will be better. For more information on apple tree maintenance view the archived Yard and Garden News article titled "Simple Steps to Productive Apple Trees" at this address http://z.umn.edu/89p.

Raspberry Renovation Workshop

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By Jake Overgaard
Extension Educator, Winona County

Jake Overgaard of University of Minnesota Extension Winona County will be giving a free on-farm workshop July 14th, from 1-2 pm on raspberry renovation at Hoch Orchard and Gardens near La Crescent, Minnesota. Participants will learn how raspberry plants develop, the importance of renovation, and how to renovate. High tunnel production will be discussed as well as variety selection. There will be an opportunity for hands-on learning (bring a pair of work gloves if interested!). The workshop will be held at Hoch Orchard and Gardens near La Crescent, Minnesota. Weather permitting, this workshop will be held entirely outdoors, dress appropriately and bring your sunscreen.

Hoch Orchard and Gardens will also be holding an open house the same day with farm tours from 11 am to 5 pm. Feel free to attend either or both events! Please see the attached flyer for directions and contact information for the open house.

Directions to Hoch Orchard and Gardens: Take Houston County Road 6 West of of La Crescent 8 miles and turn right on Forster Road. Send questions on the workshop to over0128@umn.edu or call 507-457-6440.

Seven Simple Tips to Prevent Tomato Disease

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By James Stordahl
Extension Educator, Clearwater and Polk Counties

Plants need three factors for disease to develop. The host plant must be susceptible, the pathogen must be present (usually in the soil), and the environmental conditions must be right. This typically involves wet leaves over some period of time.

Plant Disease Triangle.gif


There are several simple cultural techniques that you can implement before considering chemical treatments. Fungicides (that innocent looking white dust) are dangerous and are often over applied, so avoid using them until you have exhausted the following cultural options. Why add pesticides to your food when it can be avoided?

Step 1. Begin with a proper crop rotation. This simple practice alone will significantly reduce disease. Do not plant tomatoes where you had potatoes, peppers -- and of course tomato -- last year. Rotation is important and is your first defense in disease prevention.

Step 2. Plant a variety of tomato that is resistant or tolerant to leaf blight, especially if blight has rained on your parade in the past. Sometimes, disease can be prevented simply by variety selection. If you start your own transplants, this information is supplied on the package. If you purchase transplants, your local garden center horticulturalist will have this information.

Step 3. Do not crowd the tomatoes, lack of air circulation favors disease development. Leaf diseases need longish periods of uninterrupted wetness for disease development, and overcrowding prevents leaf drying.

Use a trellis or cage on plants spaced a minimum of 24 inches apart to keep leaves and fruit off the ground. This aids in the plant drying and keeps the disease inoculum further away from the leaves; remember, the disease inoculum is in the soil. Also, it keeps the fruit cleaner and reduces the incidence of spoiled fruit.

Step 4. This may be the single most important step of all. If you need to irrigate, water the ground, not the leaves. Sprinkler irrigation keeps the leaves wet and splashes the disease inoculum from the soil onto the leaves. Soaker hoses, drip irrigation or careful hand watering are better alternatives.

Step 5. Consider using plastic mulch. Plastic mulch laid on the soil surface prior to transplanting is a common practice in commercial production and works well in gardens too. Commercially available plastic is available in 3' and 4' wide rolls in a rainbow of colors. Clear and black are the most readily available to the gardener, but red and green are often available at garden centers. Clear and red mulch will allow weed growth beneath the plastic, unlike the black and green colors. If you need to water the plants, water through the transplant hole. Often, however, the plastic reduces water evaporation so watering is not necessary. Drip irrigation is another option when mulch is used, but increases the complexity of "simple tips".

Plastic mulch's other benefit is warming the soil, which significantly increases the yield of warm season crops like tomatoes, peppers and melons. Research in northern Minnesota shows a two-fold increased fruit yield using plastic mulch as compared to bare soil. The increased yield is due to warmer soil temperatures, reduced disease pressure, reduced water evaporation, and greater consistency in water uptake by the plant.

Step 6. Pinch off the "suckers" growing at the leaf axis. Suckers produce unnecessary foliage and decreases air circulation around the plant. Commercial growers will often leave one leaf beneath the first flower and remove all other leaf from that point and down. This does not make for a pretty tomato plant, but it's effective.

Step 7. Don't apply too much fertilizer, especially nitrogen. Excess fertilization promotes succulent leaf growth which is often more prone to disease. My fertility choice is compost, from either manure or other vegetative materials. Compost is advantageous as it provides all the essential elements necessary for plant growth in a slow release form in sync with plant growth.

If you follow these recommendations, you will hopefully enjoy juicy red tomatoes with an added benefit - fruit without pesticide residue.

If all else fails and you're tempted to use a fungicide, remember that fungicides only prevent new infections, they will not cure existing leaf disease. Fungicides should be applied according to the product label.

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