' The purpose of this manual is to teach methods of production that will result in increased yields of high quality marketable potatoes. It also teach

Transcription

1 SEPTEMBER, I947 (REVISED) CLUB SERIES NO. 21 Irish Potato Manual For 4 H Club Members Prepared By H. R. NISWONGER In Charge, Horticultural ExIension NORTH CAROLINA STATE COLLEGE EXTENSION SERVICE RALEIGH

2 ' The purpose of this manual is to teach methods of production that will result in increased yields of high quality marketable potatoes. It also teaches methods of harvesting, and grading for market and storing. REQUIREMENTS 1. Secure certified seed of either Irish Cobbler, Green Mountain, or Sequoia. 2. Plant one-half acre. Seed needed 6 Green Mountain; 8 bu. of Sequoia. bu. of Irish Cobbler or 3. Fertilizer 500 to 750 pounds of grade for western Carolina and 1000 lbs for eastern Carolina. 4. Follow cultural practices recommended. 5. Store potatoes properly for table use or when held for future sale or for seed. 6. Make an exhibit when requested. 7. Keep accurate records. Use crop record book. CULTURAL PRACTICES Seed Selection Discard seed showing dark streaks in the potato and those which are extremely large and pointed. Such seed produces low yields See Figs. 1 and 2. Fig. 1. Green Mountain Variety. Potatoes at right are distinctly oblong (flattened) and are characteristic of the variety. Those at left are not suitable for seed purposes.

3 Seed Treatment Treat seed before cutting. Mix one pound of Semesan Bel in 71/2 gallons of water. Soak seed for one minute. Dry in shade and plant. Preparation of Seed Cut the potatoes into blocky seed pieces weighing 11/2 to 2 ounces. The first cut should be made from the bud eye cluster toward the stem end of the tuber. Then the other cuts crosswise. See Fig. 3. One good eye to a seed piece is sufficient. Soils Any well drained loose soil that will produce a good crop of clover or soybeans will produce a large yield of Irish potatoes. Avoid low bottom soils which are not well drained. Avoid soils in eastern Carolina which have in the past produced potatoes infested with the southern bacterial wilt disease. The Sequoia variety does best on fertile second bottom or upland soils. Avoid planting potatoes the same year when stable manure or lime has been plowed under. Use stable manure or lime in the growing of other farm crops two or more years previous to the planting of potatoes. There will be less damage from wire worms and grubs if potatoes are not planted after a grain crop or when sod land is turned under. Fig. 2. Irish Cobbler Variety. The four potatoes at right are typical of variety and indicate high yielding qualities. Those at left, extremely large, deep eyed and pointed at ends, are off types of the variety. Preparation of land Plow the soil well in advance of planting, preferably in the fall so that any crop which has been turned will have a chance to rot before planting potatoes. A few days before planting the seed the soil should be thoroughly disked, harrowed and dragged. Soil which is cloddy will not produce a large crop.

4 Fig. 3. How seed pieces are cut. The upper potato is an Irish Cobbler. The lower is of the Green Mountain variety. Each seed potato weighs six ounces and is cut into one and one-half ounce seed pieces. Planting Dates For early crop in eastern Carolina, February and March. Piedmont area, March. Mountains, March and April. Fertilizer In eastern Carolina apply 1,000 pounds of grade per half acre. Piedmont and Mountain area, 500 to 750 pounds. Mix fertilizer thoroughly in the drill. Use a potato planter with fertilizer attachment, if available. Planting Seed Plant seed of Irish Cobbler and Green Mountain varieties 12 to 14 inches apart in row and Sequoia 9 to 10 inches. Rows of all varieties, 31/2 to 4 feet apart. Cover seed with 4 inches of soil. Cultivation Examine the potatoes to determine sprouting. Level off the ridged rows with a drag board or section harrow when potato sprouts are about one inch'long. Cultivate shallow up to time potatoes bloom and often enough to keep down grass and weeds. The potato rows may be ridged at last cultivation to provide drainage and prevent potatoes from becoming exposed to hot sun. INSECTS AND DISEASES Dust with a commercial prepared mixture containing 5% DDT. and 7% metallic copper. Begin dusting when plants are about 4 inches high and repeat every 10 days. Repeat the dusting as soon as possible after heavy rains. This dust mixture will control such insects as flea beetles, Colorado potato and blister beetles and late blight and other leaf spot diseases.

5 HARVESTING Harvest the potatoes during the cool part of the day to prevent sun scald. Use a mechanical digger if available. GRADING Avoid rough handling in grading, sacking, and loading for ship-. ment. A No. 1 grade consists of potatoes of one variety, smooth, carefully sorted, free from second growth, sun scalds, cuts, diseases, and insect or other injury. The minimum diameter of potatoes should be 17/3 inches unless otherwise specified in the U. S. grades. STORING Irish potatoes keep best in a dark and relatively dry cellar or building in a temperature of 38 to 40 degrees. Store in slatted crates or in bins. When stored in bins the potatoes should be stored not over three feet deep and over a slatted floor. Small quantities may be stored in banks or pits and protected from excess moisture and freezing. In Eastern Carolina the early crop may be kept for a limited time in a cool building. Write the Agricultural Engineering De partment, N. C. State College for air-cool-storage plans for Irish» potatoes. EXHIBITS Potatoes selected for exhibit purposes should be true to type and uniform in size. They should be smooth and free from scab and other blemishes. The skin should be bright and typical of the variety. Medium or marketable sized potatoes are preferred. Medium sized potatoes will weigh around eight ounces. Select the potatoes in the field at harvest time. Selecta tuber which is typical of the variety and match others with it. Pick more than is necessary for the exhibit. Wrap each potato separately in paper in order to prevent bruising the tender skin in moving to the storage. Make the final selection of tubers from the stored lot just before sending to the ShOW. Each potato should be as nearly alike in size, color, and shape as possible. Brush each potato with a soft bristle brush to remove dirt from the skin and eyes. Wipe with a soft cloth. Exhibit potatoes in trays. Place potatoes in trays two layers deep. The dimensions of trays are 111/2 x 18 x 3 inches inside measurement. ~

6 SCORE CARD RATING Uniformity (size, shape, color) Type (shape, color) Freedom from blemishes (cuts, bruises, insect and disease damage) Size, marketable standpoint Depth and number of eyes Total BASIS OF AWARDS Yield of U. S. No. 1 Grade Exhibit Cost of production and profit Record and story Total NORTH CAROLINA STATE COLLEGE OF AGRICULTURE AND ENGINEERING OF THE UNIVERSITY OF NORTH CAROLINA AND U. S. DEPARTMENT OF AGRICULTURE, COOPERATING N. C. AGRICULTURAL EXTENSION SERVICE I. O. SCHAUB. DIRECTOR STATE COLLEGE STATION RALEIGH DISTRIBUTED IN FURTHERANCE OF THE ACTS OF CONGRESS OF MAY 8 AND JUNE