PINEAPPLE IN HAWAII
Total land area on the islands and its utilization are shown in the following two tables.
Land area in Hawaii by island. __________________________________________________________ Island Square miles Acres __________________________________________________________ Hawaii 4,038 2,584,000 Maui 729 466,000 Oahu 698 388,000 Kauai 553 354,000 Molokai 261 167,000 Lanai 139 89,000 Niihau 73 46,000 __________________________________________________________
Land use in Hawaii, 1993 estimates. _________________________________________________________________ Use Acres* _________________________________________________________________ Urban, industrial, military 123,000 Parks 246,000 Waste land (lava, canyons, mountains) 698,000 Forest (not grazed by animals) (estimate 1,487,000 Pastures (estimate) >1,000,000 Other 63,000 Agricultural crops Sugarcane 121,100 Pineapple 22,300 Vegetables and melons 5,300 Fruits (excluding pineapple) 6,600 Coffee 6,800 Macadamia 20,200 All other** 5,500 ________________________________________________________________*Statistics of Hawaiian Agriculture, 1994
**taro, seed corn, flowers, ornamentals, feed & forage, nursery products.
The actual date of introduction of pineapple (Ananas comosusL.(Merrill) into Hawaii is not known. Pineapple was discovered by the Spanish in Central America and it was spread widely by explorers from Spain within a hundred years or so. Pineapple was grown in Hawaii as early as 1813 but planting on a fairly large scale did not begin until after 1850. The first commercial venture was near Kailua on the island of Hawaii. It was short lived, however, and it was not until the middle 1880's that a significant industry began to develop. James Dole established a plantation in the Wahiawa area of Oahu about 1900. The industry was well organized on several islands by 1915 to 1920; growth of the industry peaked in the 1950's and then declined slowly under pressures of lowered prices resulting from international competition until the mid- 1970's when acreage stabilized. Acreage has declined further in the last few years.
Pineapple (almost entirely Smooth Cayenne) is grown primarily on Oahu and Maui. Because of its efficient use of water, the crop is grown in areas having relatively low rainfall (from 20 to 80 inches annually). In the past, irrigation was only used during very dry periods or in very dry areas. Recently, drip irrigation has been adopted to supply water and to inject nutrients and nematicides into the root zone after planting. Drip irrigation is now a wide-spread practice in the industry. Irrigation may actually be detrimental in higher rainfall areas because wet soil conditions favor root rot organisms, primarily the Phytophthera spp. Fungicides are now available to effectively control this problem.
Pineapple is grown at elevations ranging from sea level to about 700 meters (2,600 feet) on Maui and from 150 to 460 meters (500 to 1500 feet) on the other islands. Most field practices are mechanized which helps to make Hawaii's pineapple competitive in price with fruit produced in Thailand and the Philippines where labor costs are much lower. Planting material, mostly crowns from the top of fruit, is collected at the time fruit are harvested. Planting is done entirely by hand and harvesting is done by hand but the fruit are transported from the field to the truck by a self-propelled conveyor belt. All other field operations are done with machines. The field practices are briefly summarized below.
Soil PreparationAfter the last harvest, the old plants are disced several times, left to dry, and then burned or plowed into the soil. Soil preparation usually includes plowing with a moldboard plow to a depth of 18 to 24", followed by discing. Discing breaks up soil clods to assure that soil fumigants used to control nematodes penetrate throughout the soil. After tillage, preplant fertilizer consisting of a mixture of N, P, and K are applied, a fumigant to control nematodes is injected into the soil, and plastic strips are laid over the fumigated area, all by one machine. All P and most of the K is applied prior to planting. The plastic serves several purposes; it is marks the plant location, it retains the fumigant, it controls weeds under the strip, and it raises soil temperature resulting in a sizeable increase in plant growth rate during the cooler winter months.
PlantingPlanting material consists of crowns from the top of the fruit, although slips which come from the base of the fruit, and suckers pulled from the base of the plant stem may sometimes be used if planting material is in short supply. Usually planting material is dipped in a fungicide or dried in the field for several days prior to planting. Dipping or drying reduces the incidence of root and heart rot after planting. Planting is mostly done by hand. Usually more than 24,000 to 30,000 crowns or other propagules are planted per acre, with a higher density being used if the fruit is to be harvested for sale as fresh fruit.
Water ManagementWater is applied by overhead boom spray or sprinkler to establish plants if no rains are likely. In the drier areas of Maui and Oahu, drip irrigation helps to maintain growth rates. Water is applied approximately once weekly.
Post-plant FertilizationNitrogen, as urea or urea-ammonium nitrate, iron and zinc are commonly applied after planting. All nutrients applied after planting are applied by a boom spray truck or with the irrigation water. A urea, iron, and zinc solution is applied every ten days to two weeks beginning about three months after planting until fruiting is initiated.
Crop HazardsWeed, insect and disease problems are all encountered in the production of pineapple. Weeds are controlled by spraying herbicides with the boom spray truck. Pineapple tolerates some potent herbicides so weeds are not a serious problem beyond their cost of control. The major insect problem is the mealybug which is tended and protected on pineapple plants by ants. An effective ant control program makes it possible for the mealybug to be kept under control by biological means, mostly by predation, and ant control costs usually are less than those incurred in controlling mealybugs. There are no insects that attack the pineapple fruit in Hawaii at the present time. Diseases of pineapple include root rot and heart rot caused by Phytophthera parasitica and P. cinnamomi, interfruitlet corking caused by species of Fusarium and Penicillium fungi, and pink disease caused by a bacteria.
Heart and root rot are controlled by a preplant dip and by postplant sprays where problems are expected to be severe. Root rot is also controlled to some degree by keeping soil pH low, in the range of 4.5 to 5.5. While some losses due to fruit diseases occur, they are not large enough to justify the costs of control even though annual losses may reach $5 million. All agricultural chemicals applied to pineapple are put on with the boom spray truck.
Flower InductionPineapple is the only crop where complete control of the life cycle is possible. Flowering occurs naturally in Hawaii during December but flowering is seldom uniform. Uniformity of flowering is achieved using ethylene, a gas, adsorbed on activated charcoal in water, or ethephon. The chemicals are all applied with the boom spray truck. Generally, greater than 95% of the plants develop an inflorescence after application of the growth regulator.
Fruit RipeningFruit ripening can also be controlled by application of ethephon with the boom spray truck. A first harvest often is made to collect fruit that ripens early and any remaining fruit are induced to ripen by the application of ethephon. A second harvest is made about a week after ethephon is applied.
HarvestingHarvesting is accomplished by workers who follow a self-propelled boom that extends into the field and conveys the picked fruit to bins in a truck. If the fruit is to be sold fresh, it is dipped in fungicide to control rot and packed for shipment. After fruit from the mother plant is harvested, a second or ratoon crop develops on suckers produced on the mother plant stem. The plant crop takes 18-20 months to mature while the ratoon crop is produced in only an additional 12 months. Much of the profit is realized from ratoon crops because the costs of field preparation, planting, and weed control have been paid for by the mother plant crop.