Principal Investigator: Cindy Hale, Clover Valley Farms
Keywords: apples, trellis, rootstock
Over 3 years, 11 trial orchards were established in nine sites along the shore of Lake Superior in northern Minnesota to demonstrate high-density trellised apple production and trial different rootstocks with modern and historic apple varieties.
The primary project objective is to support production of apples using organic, sustainable, and Integrated Pest Management (IPM) strategies among small farmers in northeast Minnesota. We will emphasize strategies to maximize production and profit in consideration to the climate, soil, and landscape constraints and the reduced pest pressure that north shore growers experience. Production, climate, and IPM data will be collected annually at each site and shared through workshops, field days, Clover Valley Farms’ website, and through collaborations with local and regional farming organizations.
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Clover Valley Farms
6534 Homestead Rd, Duluth MN 55804
Saint Louis County
2014 to 2017
Cindy Hale and Jeff Hall of Clover Valley Farms, LLC operate a small, diversified farm on 25 acres just north of Duluth. Enterprises on the farm include direct sales of pastured poultry, hogs, and sheep (fleece), a year-round solar greenhouse, and gardens and orchards for vegetable, herb, and fruit production.
High-density apple orchards, using cold-hardy super dwarfing rootstocks, can be used to develop profitable enterprises for small farmers along the north shore. Along the north shore, including St. Louis, Lake, and Cook counties, apple production was limited due to the unavailability of large tracks of land needed for traditional orchards. In addition, the soil and landscape conditions along the north shore did not create a desirable environment for apple production. A vibrant organic apple grower network in the region could support the development of local markets with the economic, ecological, and health benefits for farms and consumers, similar to benefits seen on the south shore in Bayfield, WI. Cindy, with the help of Diane Booth from Cook County Extension, is leading a three-year project to provide annual field based trainings on high-density apple production, implementing organic and IPM strategies, and assistance for producers to gain access to locally adapted apple varieties and other resources. These trainings will help to develop small-scale orchards, which are part of a more healthy and sustainable local food system.
Organically managed, trellised high-density orchards in other regions of the western Great Lakes are well established. Therefore, resources exist to help develop similar orchards along the north shore. Existing modern and heritage apple varieties provide disease resistance and fruit diversity for fresh eating and value-added products. Recently completed genetic work is beginning to identify undescribed, historic apple varieties that are well adapted to local conditions. However, a lack of grower support and organization has been an obstacle for small producers to implement high-density orchard systems and to acquire historic apple varieties.
At Farmer-to-Farmer Exchanges held by Cook County Extension, more than 30 local farmers gathered in Grand Marais to discuss local food system needs and opportunities for the area. There was particular interest in issues related to climate change for small-scale agriculture along the north shore. Five issues emerged that relate to the project:
Two existing orchards will provide baseline IPM and production data, including Clover Valley Farms with approximately 1 acre in apple production using M-7 and Bud9 rootstock with six modern and 12 heritage varieties. Ray Block, with a high-density orchard containing 1, 2, and 3 year old blocks (162 trees) using Bud9, G11, G16, and G30 stock with Honeycrisp, Zestar!, and Chestnut Crab on each.
IPM monitoring documented a very late and cold spring from which the region never fully recovered. Between April 1 and September 29, only 915 growing degree days (GDD) were documented at the Duluth site. Late establishment of the IPM data loggers in Grand Marais did not allow for seasonal GDD measurements. Anecdotal observations indicated a much cooler and shorter growing season in Grand Marais than was observed in Duluth. Apple scab models did not indicate high probability of infection until early June. Both established orchards chose not to spray for apple scab since little field evidence of primary scab infection existed and model predictions indicated that most of the scab spores had already been spent. Very low levels of primary and/or secondary apple scab were detected during summer scouting and fall harvest. This season, the most economically impactful pest issue was Lesser Apple Worm at the Duluth site. As an internal feeder, it is difficult to treat. Pest trapping indicated larger than average populations and at least two generations, which resulted in substantial damage to mature fruit. Future control options to address this pest need to be considered for future years. There were also very high populations and multiple generations of Oblique-Banded (OBLR) and Red-Banded Leaf Rollers. These pests were easily controlled with Bt sprays that were guided by trapping and GDD models to appropriately time applications. This resulted in no significant economic impacts.
Production in these orchards varied with the seasonality of the varieties that were old enough to produce. For example, Zestar! are present but not yet in production. Despite the challenging weather, all of the early season apple varieties, such as Honeycrisp and Norland Red, produced high quality, mature crops suitable for the fresh eating market. Later season varieties, such as Frostbite and Haralson, did not reach full maturity before cold fall temperatures. However, these crops were still able to be used in value-added products such as sweet cider and sauces.
Four new high density orchards were established in 2014 with a total of 174 trees planted. Due to the late spring and other issues starting the project, these orchards were planted at different times and later than ideal. Even with these circumstances, all of the orchards seemed well established by fall. Trellising the orchards will be completed in spring 2015. Trees used in these plantings included approximately 80 that were bench grafted in March 2014. The rest of the trees used were purchased from a regional nursery.
In mid-June, Clover Valley Farms planted 50 newly grafted trees on Bud9 rootstock. This included 15 described varieties (Redwell, Dutchess, Frostbite, St. Edmunds Russet, Hazen, Prairie Spy, Haralson, Northern Spy, Ashmed Kernal, Blue Permian, Black Oxford, Whitney Crab, Wealthy, Famuse Snow, Parkland, and Oriole) and four previously unnamed varieties (Allure’s Wild Red, Barb’s Bounty, Justin’s Jewel, and Gitchee Gummi Golden). Paul Kotz and Susanne Hoderried, in Grand Marais, planted a total of 50 trees using eight described varieties on various rootstocks, including: Honeycrisp (on rootstock Bud9 and G-16), Zestar! (on Bud9 and G-11), Snowsweet (on G-30), Sweet 16 (on Bud9, G-16 and G-41), and Dolgo and Kerr Crab Apples. The orchard was planted in early July and was irrigated well throughout the summer. All trees appeared to be in good condition at the end of the season. Dave Williams, in Grand Marais, planted a total of 46 trees using five described varieties on various rootstocks including Honeycrisp (on rootstock Bud9 and G-16), Zestar! (on Bud9), Snowsweet (on G-30), Sweet 16 (on Bud9, G-16 and G-41), and Kerr Crab Apple. These trees were planted July 18. Several of the spring grafted trees that had failed spring grafts were bud grafted in August. All trees appeared to be in good condition at the end of the season. Stan Bautch, in Grand Marais, planted a total of 28 trees including Honeycrisp (on rootstock G-16), Zestar! (on Bud9), and Whitney Crab or Allure’s Wild Red (on Bud9). These trees were planted on August 11. All trees appeared to be in good condition at the end of the season.
In addition to the IPM monitoring stations in Duluth, two more stations with data loggers and pheromone pest traps, have now been established in Grand Marais. Additional pest trapping data was collected by the City of Duluth and submitted to this project. Substantial differences in pest pressure and GDD were documented between Duluth and Grand Marais.
Pest trap data showed that coddling moth was detected in Duluth, but not at Clover Valley Farms or Grand Marais, indicating that this pest remains geographically excluded from most of northeastern Minnesota. For the second year, large early summer populations of OBLR were detected in Duluth. Bt sprays were successful in limiting late season populations and preventing potential economic damage. Further, early detection of OBLR in Duluth gave Grand Marais growers the opportunity to watch out for early detections of the pest. Apple Maggot populations were low all season along the North Shore. However, it remains one of the most challenging pests to manage organically and poses one of the most substantial economic threats to fresh eating apple production in the area. Lesser Apple Worm, an internal feeder that is difficult to manage, was detected again this year in Duluth and Grand Marais. However, in 2015 there was less fruit damage than 2014 with similar trapping rates. Consideration for future monitoring and control options to address this pest is needed in the future.
In stark contrast to the late and cool 2014 growing season, Duluth experienced early warmth. The warmth continued into November, which resulted in 1,750 GDD. Grand Marais had approximately 1,300 GDD this growing season.
Annually, apple scab models indicated medium to high probability of infection starting in early June through September. However, the pattern of potential infection windows and spore levels predicted by the apple scab models varied greatly from the three data logger locations. This is valuable in predicting potential real infection windows and useful for directing management decisions (i.e. to spray or not spray). For instance, little apple scab was actually detected in Clover Valley Farms’ orchards and no spraying for apple scab was done because 1) little field evidence of primary scab infection existed and 2) model predictions indicating that most of the scab spores had already been spent by the time periods of likely infection conditions were observed. Very low levels of primary and/ or secondary apple scab were detected during summer scouting and fall harvest.
Production in the orchards, which are old enough to produce a crop, was early and abundant. In Duluth, early season varieties were ripe in July. Mid-season varieties, such as Honeycrisp, were ripe in late September. The late season varieties, such as Honeygold and Haralson, ripened in October and November. In Grand Marais, the late season apple, with a very long window of ripening, did not reach full maturity before cold fall temperatures. However, these crops were still used in sweet cider and sauces.
This season, 306 trees were established in seven orchards. There are five orchards in Grand Marais, one in Duluth, and one in Carlton County.
A total of 680 trees have been secured for this project so far, including the following:
The trees that were not planted are at Clover Valley Farms. They will be used by the project in 2016. Rootstocks that have been established in these demonstration orchards include Bud9, G-11, G-16, G-30, G-41, and G-935. For comparison, both Ray Block’s orchard and Clover Valley Farms’ orchards contain semi-dwarf M-7 stock with a range of varieties.
There are 24 described apple varieties that have been established in the demonstration orchards. The varieties include Ashmed Kernal, Black Oxford, Blue Permian, Brown Snout (cider apple), Chestnut Crab, Dolgo Crab, Dutchess, Famuse Snow, Frostbite, Haralson, Hazen, Honeycrisp, Kerr Crab, Northern Spy, Oriole, Parkland, Prairie Spy, Redwell, St. Edmunds Russet, Snowsweet, Sweet 16, Wealthy, Whitney Crab, Yellow Transparent, and Zestar!. Five previously unnamed historic varieties that have been established in the demonstration orchards include Allure’s Wild Red, Barb’s Bounty, Justin’s Jewel, Gitchee Gummi Golden, and Northern Exposure. The previously unnamed varieties were identified in local historic orchards and genotyped in 2013. They did not match any known variety in the USDA database available, so they were assigned new varietal names. It is the intention of this project to continue propagation and distribution of these heritage varieties beyond the close of the study.
Heritage apple genetic samples were collected this year from 58 trees. They were submitted to Dr. Briana Gross at UMD for genetic typing. The objective is to identify historic apple trees, which are trees that are over 100 years old, that may be potentially valuable, locally adapted, unnamed apple varieties that growers may want to propagate. Results are anticipated in spring 2016, which will give us the final year of the project to collect scions and preserve these historic apples.
Pest Trap Data showed that coddling moth is regularly detected at low numbers in the city of Duluth but not at Clover Valley Farms or Grand Marias, indicating that this pest remains geographically excluded from most of northeast Minnesota. As with last year, large early summer populations of OBLR and LAW were detected in Duluth and Grand Marias. Organic Bt sprays were successfully used to limit late season populations of OBLR and potential economic damage. Further, early detection of OBLR in Duluth gave Grand Marais growers an opportunity to be on the watch for early detections of this pest. The large populations LAW this year turned out to not have significant ecological or economic damage to the apple crops, but provide good evidence that annual monitoring is important. Apple Maggot was nearly absent in trapping counts this year.
This year was another early and warm year with Duluth showing a total of over 1,800 GDD with a growing season that continued into early November. Early season apples in Duluth were harvestable in August and even later season apples reached good maturity by the end of the growing season. In contrast Grand Marias had a cooler and later spring than Duluth and finished the growing season in September at 1,190 GDD, again demonstrating that growing season is the most limiting factor for apple production in that area.
Apple scab models and observed levels of infection varied annually during the project. Apple scab appeared to be less of a problem in the newer, smaller, and more isolated orchards in Grand Marias than those in Duluth. This year, early wet and warm conditions predicted high likelihood of apple scab infection in June at Clover Valley Farms. Therefore, a sulphur-lime spray was used which appeared to largely control primary apple scab in that orchard. In other local orchards, and in the City of Duluth, where no spraying was done, apple scab infection was heavy leading to substantial crop damage and loss.
None of the trees planted as a part of this study were producing yet. However, establishment and growth of most trees was excellent and they look poised for a good first crop in 2017. In the two orchards, which had established trees prior to the start of this project (Clover Valley Farms and Ray Block) fruit production was again abundant. The quality of the fruit was exceptional, likely due to the “just right” combination of warmth and rain. Fruit load management will be important as the newly established orchards begin producing to prevent physical damage to trees from heavy crop loads. In Duluth, early season varieties were consistently ripe in late July to early August including, but not limited to, Yellow Transparent, Norland Red, Allure’s Wild Red; mid-season varieties (i.e. Honeycrisp, Zestar! ) were ripe in September; and late season varieties (i.e. Honeygold, Haralson, Frostbite) ripened in October-November. In contrast, the general pattern for Grand Marias’ apples was a later start with trees blooming well into May. As a result later season apples with a very long window of ripening, had not reached full maturity before cold fall temperatures. However, these crops were still useable in value-added products. Ray Block has been experimenting with putting high tunnels over Zestar! and was able to get full bloom almost a month earlier than trees in the same orchard that were not under tunnels. By leaving the ends of the tunnels open, he had great pollination as the local pollinators found these trees and were very actively using them before the unprotected trees had bloomed.
Additional blocks of trees were added to two sites, including: three 20-30 tree blocks at Clover Valley Farms and approximately 100 new trees to the Stan Bautch orchard.
Heritage Apple Genetic Samples that were submitted to Dr. Briana Gross at UMD for genetic typing, found that four trees were identified as previously described varieties (i.e. 1- Beacon, 1-Yellow Transparent, 2-Oriole) and three undescribed varieties were represented in two to four different sites. These may represent local developed apples worthy of further description and propagation.
Please contact the owners if you’d like to see their orchards.
To the Clover Valley Farms site, take 35 north from Minneapolis/St. Paul towards Duluth. Exit onto MN-61. Turn left on Homestead Road.
Stan Bautch’s Orchard is in downtown Grand Marais and easily visible from the road. On the corner of Fifth Street and County Road 7 in Downtown Grand Marais, MN.
To the Lake Superior Orchard site, take 35 north from Minneapolis/St. Paul towards Duluth. Exit onto MN-61. Bear right onto East Rosebush Lane.
To the Paul Kotz & Susanne Holderried site, take 35 north from Minneapolis/St. Paul towards Duluth. Exit onto MN-61.
To the Rosebush Creek Ranch site, take 35 north from Minneapolis/St. Paul towards Duluth. Exit onto MN-61. Turn left onto Fall River Road.
To the Erik Hahn site, take 35 north from Minneapolis/St. Paul towards Duluth. Exit onto MN-61. Turn left on Cty. Rd. 14. Turn right onto Caspers Hill.
To the Northern Harvest Farm site, take 35 north from Minneapolis/St. Paul towards Duluth. Take exit 227 towards Mahtowa/Wrenshall. Turn right onto County Road 4. Turn left onto Mahtowa Road. Turn right onto Military Road. Turn right onto County Road 102.
University of Minnesota, Minnesota Hardy - Apples
Minnesota Department of Agriculture, Integrated Pest Management Program
Michigan State University, Integrated Pest Management Program
Organic Fruit Growers Association
eXtension.org - Apples
Cornell University - A Growers Guide to Organic Apples
National Sustainable Agriculture Information System
University of Wisconsin-Madison, Center for Applied Agricultural Systems
Ag Marketing & Development Division