Armstrong Farm Field Day - June 27th

Area residents are invited to “come to the farm” - the ISU Armstrong Research Farm - on Friday, June 27. The 2008 field day begins with registration at 9 a.m. with wagon tours at 9:30 a.m. Tour stops will feature soybean fungicides by Allison Robertson, ISU Plant Pathology. Roger Elmore, ISU Agronomy, will give a presentation on corn hybrids by cropping systems. Beef feedlot runoff systems will be presented by Shawn Shouse, ISU ag engineering specialist; and, Paul Domoto, ISU Horticulture, will give an update on vineyard trials. Lunch will be available following the tour. Drinks will be furnished by Farm Credit Service. The Armstrong Research Farm is located 13 miles southwest of Atlantic on Highway 6, one-half mile south on 525th Street, and three-quarters of a mile east on Hitchcock Avenue.

GARDEN FIELD DAY
August 9, 2006

photos courtesy of Rex Galloway

The Wallace Foundation was formed in 1990 to enhance agricultural research and education for Southwest Iowa. The Armstrong Research and Demonstration Farm was established by a donation of 40 acres and the sale of 360 acres to the foundation by Gail and Glendale Armstrong in 1993.

Research

• Crops. Row crop and forage management studies focus on corn and soybean row spacing, strip-cropping, insecticide and herbicide trials, planting dates and populations, and weed managment.
• Soil. Agronomists study potassium and phosphorus application rates and placement and their effect on soil fertility and crop yields. They also study timing and rates of nitrogen, lime and manure on row crops. The topography of the area makes soil erosion and tillage work important.
• Livestock. Researchers study sustainable livestock production methods. Animal scientists conduct beef nutrition, health and management studies. Beef cattle are in rotational grazing and forage utilization trials. An alternate deep-bedded breed-to-wean swine production system is studied at the farm.

Facilities

• A cattle-feeding research unit was completed in 1995. Pastures and forage feeding equipment support rotational grazing studies.
• The 9,500 square foot Wallace Learning Center features an Iowa Communication Network classroom and meeting place for up to 150 people.

Introduction
Home demonstration gardens were located at ten sites across the state. The theme was a garden for the birds and included beets, baking potatoes, slicing cucumbers, and a hybrid super sweet corn. Many varieties of annual vinca and sunflowers were also grown.

Limited fertilizer and pesticides were used. Plants were watered at planting and then as needed throughout the growing season.

Nine different flowers were grown for the gardens for the birds. Also included were 12 cultivars of sunflowers. Transplants of five vinca and slicing cucumber cultivars, eight cultivars of baking potatoes, and beets, and six cultivars of super or "triple" sweet corn were grown at each participating farm.

Results and Discussion
Due to the cool spring weather, many of the vegetable and flower varieties were slow to establish themselves. Seeds of sorghum, safflower, cleome, and millet germinated poorly at several farms. The cool temperatures also contributed to the late harvest on sweet corn varieties.

Vegetables. The potato varieites grown included Superior, Caribe, Viking Red, Island Sunshine, Red Gold, Red Lasota, Carola (Carole), and Russian Banana. All potato varieties produced sizable tubers at each farm. Yield data for the Armstrong Farm is presented in Table 1. Cultivars that produced well included Superior, Red Gold, Carola, Red Lasota, Viking Red, and Russian Banana.

Cucumbers were also productive at most farms. The cultivars grown included Sweet Slice, Thunder, General Lee, Fanfare, Diva, and at a few farms, Cobra. While General Le, an older variety, was the most productiVe at the Armstrong Farm (Table 2), many field day attendees preferred the taste of the newer cultivars of Sweet Slice or Diva.

Data were not collected on the beets or sweet corn grown at each farm. Beet cultivars grown were Cylindra, Egyptian Flat, Burpee's Golden, Detroit Dark Red, Ruby Queen, Bull's Blood, Blankoma White, and Chioggia. All beet cultivars were productive with the exception of Burpee's Golden, which germinated poorly at several farms. Informal taste tests conducted during field days noted that Chioggia, Blankoma White, Detroit Dark Red, and Burpee's Golden were popular varieties.

Super sweet corn cultivars grown included Avalon, Honey Select, Serendipity, Nantasket, Providence, and Cinderella. All are triple sweet hybrid varieties new to the market. Unfortunately, all were also harvested late in the season. Informal taste tests at one research farm were highly variable and no single cultivar was preferred.

Flowers. The sunflower cultivars grown were Joker, Italian White, Starburst Lemon Aurora, Giant Sungold, Moulin Rouge, Tiffany, Claret, Soraya, Valentine, Ring of Fire, Ruby Moon, and Stella Gold. All sunflower cultivars performed beautifully at each garden except Stella Gold and Giant Sungold, which were late in producing flowers.

The vinca series grown at each garden included Cooler, Heatwave, Pacifica, Merry-Go-Round, and Mediterranean. All were equally beautiful and bloomed repeatedly throughout the summer.

Acknowledgments
The contribution of time and labor throughout the duration of this project by the ISU Research and Demonstration Farms office and each participating farm was greatly appreciated.

Comparison of different slicing cucumbers grown at Armstrong Research and Demonstration Farm in Lewis, Iowa.

Total Number Total Weight Average fruit weight
Variety fruit (pounds) (pounds
Sweet Slice 183 176.7 0.97
Thunder 187 147 0.79
General Lee 203 145.9 0.72
Diva 71 44 0.62

Evaluation of Two Soil Amendments

Introduction
For many years, home gardeners have recognized the benefits of applying compost and other soil amendments to their soils. Though not considered a fertilizer by industry standards, compost is universally recognized for improving structure, water-holding capacity, and the nutrient content of our soils. In many gardening systems, including both organic an conventional, compost is often the major soil enrichment product. On occasion, other soil amending product, such as humic acid, have been tried by gardeners in hopes of achieving many of the same benefits of compost, but with less volume and cost.

When compost has been applied at recommended rates to low fertility garden soils, it has consistently increased vegetable yields and improved soil fertility. Less is known about the benefits of adding humic acid to Iowa soils. Considering the fact that many Iowa home gardens contain soils testing in the high range for fertility, one might question if the additional soil amendments to these soils would prove effective.

Methods
In 2003, a study was conducted at the Armstrong Research Farm to evaluate the benefits of two soil amendments on a soil that tested high in fertility Table 1). Recommended rates of municipal yard waste compost from a local recycling facility and a commercially marketed humic acid product were applied to five vegetables to evaluate their effect on crop yield and soil fertility. Both soil amendments were applied preplant and worked deeply into the soil with a tiller. A second sidedress application of the humic acid was applied in midsummer as per label instructions. The application rate per 100 ft(2) was 480 lb for the compost and 1.5 lb for each treatment of humic acid.

The site selected for the garden was a Marshall silty clay loam with an organic matter of 4.2% and a cation exchange capability (CEC) of 17-1 mEq/100 g. Potatoes, onions, green beans, sweet corn, and tomatoes were planted in a completely randomized block design with four replications. Each individual plot consisted of one row, 8 ft in length. Urea nitrogen at a 100 lb/acre rate was applied as a sidedress to the sweet corn plots at the V 5 stage. Weekly applications of the fungicide Bravo 720 and insecticide Sevin XLR were applied for disease and pest control. Weed control was achieved through cultivation and hand weeding. The tomato plots were caged and mulched. No irrigation was made available to the garden.

Results and Discussion
Growing conditions throughout the season were favorable and yields were good for all crops. Yield results for the five vegetables tested are presented in (Table 2). The compost treatment increased the total yield and size of four of the vegetables tested, while the humic acid treatment was effective on to. Both soil amending products were effective on the potato and tomato crops, while neither was effective on the onion variety tested. The yield responses with the compost treatment were quite large, ranging from 18 to 45%, with the tomato and potato crops providing the greatest responses for both products. In most cases the yield increase was the result of both an increase in fruit size and number. Interestingly, the compost treatment caused a delay in the maturity of the green bean variety, while at the same time it increased the early harvest of the tomato variety.

Soil samples taken at the end of the growing season (Table 1) indicate that the humic acid treatment had little effect on the soil fertility measurements taken, while the compost treatment caused all the soil phosphorous, potassium, and organic matter levels to rise.

Based on this one-year study, it is apparent that many garden vegetables will indeed respond to certain soil amendments, even in a high-fertility environment. The yield responses were larger and more consistent for the compost treatment, and only the compost treatment increased soil fertility levels. What is not apparent from this study is exactly which soil property was affected by the soil amendment and thus caused the yield increases. Did the soil amendments increase soil nutrients, water, holding capacity, density, porosity, or microorganisms? Further experiments would be needed to explore this question.

Acknowlegments
We would like to thank Gorden Andersen of Oma-Gro for providing the compost and Dave Williams of Malone's Garden Center for providing the humic acid for the study. Also, thanks to the Armstrong Farm staff for their help in harvesting the trials.

The Wallace Foundation for Rural Research and Development serves residents of the following counties:

Adair - Adams - Audubon - Cass - Carroll - Clark
Crawford - Decatur - Fremont - Guthrie - Madison
Mills - Montgomery - Page - Pottawattomie
Ringgold - Shelby - Taylor - Union