Weed Control Methods For Recreation Facilities Management

Edward O. Gangstad, Gangstad

• Publisher: CRC Press
• Year: 2018
• Print ISBN: 9781315898605
• eBook ISBN: 9781351094603
• Topic: Biological Sciences
• Subtopic: Biology
• Index: Biological Sciences

It is the purpose of this volume to survey and assess the management problems of recreation waters and to present case problems from the field in which the technical data, published literature, and the operations mechanics are given in sufficient detail to provide a format for practical analysis and application. Special emphasis has been given to measures of control of Eurasian watermilfoil.The primary and secondary uses of a body of water determine the need, frequency, and kind of aquatic plant control required to meet the needs of a specific situation. That is to say, a given body of water may be used primarily, or even exclusively for such activities as fishing, boating, or swimming, and the water itself may be used for domestic (potable water), industrial production, and/or agriculture. These uses may seem to be incompatible in themselves, but it is incumbent upon management to supply the optimum conditions for total water use.

Part I: Special Studies for Management of Recreation Waters

Chapter 1

COSTS AND BENEFITS OF AQUATIC WEED CONTROL

INTRODUCTION

Recurring floods and droughts have been natural phenomena since prehistoric times. With the advent of man and his civilization of cities, cultivated farms, and industrial development, water storage and impoundment have become a vital necessity. While it is widely recognized that aquatic weeds can cause considerable damage in these water resource areas, thereby retarding economic growth, there has been little serious attempt to quantify, estimate, or even define the extent of the weed nuisance in terms of specific economic losses. Therefore, a sound basis for determining the priority among competing demands on limited resources that should be given to aquatic weed control programs has not been developed.

It is clearly not possible to define economic losses in exact dollar terms. Precise information does not exist nor could it readily be developed concerning the damage caused by specific weeds in specific settings, let alone the overall impact, including secondary effects, on an economy. Instead, an attempt is made to develop order-ofmagnitude estimates for selected types of damage caused by weeds in specific settings. Such broad estimates should at least place the problem in better perspective and provide some guidance as to the priority that should be attached to corrective action in this field.

The damage and problems caused by weeds can have, in varying degrees, a negative effect upon a country’s economy. Whereas a developed country, such as the U.S., can readily absorb such economic losses, as has happened in Florida, Louisiana, Mississippi, and Georgia, such losses cannot be easily accepted in a developing country. Countries which have only one, or a few, waterways or other fresh-water bodies can be more seriously affected than “wetter” countries with much fresh water and an extensive riverine network. In countries bordering the Niger, the Congo, or the Nile Rivers, for example, weeds can be a very serious potential threat to the overall economy. Even in the “wetter” countries such as Ceylon, India, Guyana, and Brazil with many ancillary waterways, massive weed infestation will, with time, have measurable economic consequences, especially where the major rivers are prime avenues for transportation, sources of food, or hydropower. The economic loss resulting from disease is particularly difficult to assess, even in societies where collection of complete and accurate demographic and social data is a well-established practice. In many of the larger semiarid countries roads, railroads, or air networks provide extensive transport linkages at reasonable cost. However, this approach is prohibitive for some of the delta or savannah countries where dense jungle or hills impose serious physical obstacles to land transport or airport construction.

ECONOMIC IMPACT

Some attempts have been made to assess the impact of weeds upon the economies of Florida and Louisiana which may give some baseline for estimating losses in developing countries. Even as far back as the turn of the century, when the embryonic hyacinth infestation plagued Florida with Lake George being blocked by hyacinths for 40 km, an annual loss to the lumber trade alone of $55,000 was estimated. Transport by water is still a vital factor in the economy of the Mississippi delta since corn, rice, cane, and cotton together with fish, citrus fruits, salt, oil, lumber, and other products are carried by water. The water hyacinth invasion has thus had serious consequences, and it has been estimated that the annual loss incurred in Louisiana through the effects of the weed reached $35 million annually in recent years from damage to agriculture, fish and wildlife, navigation, drainage, and public health.

Aside from such roughly estimated direct economic losses, there are additional costs of deliberate weed removal and prophylactic measures for growth prevention. Such costs, which may amount to millions of dollars per year, are incurred just to keep the weeds under some level of control and prevent further economic damage. Since 1959 the Corps of Engineers in Florida has received about $3.6 million annually for hyacinth eradication programs in Florida to which is added a 30% matching contribution by the state. That sum, however, is not all that is being spent. In addition, in 1969, the state of Florida spent $1.3 million for control efforts, and for fiscal year (FY) 1970, $2.5 million was requested by the Governor’s Aquatic Weed Research and Development Committee because control attempts had not been very successful.

The economic losses estimated for the U.S. are, at best, rough estimates prepared by federal, state, and local organizations concerned with budgets. While these estimated dollar losses represent the principal “hard” data available for any country, they are difficult to apply directly to developing country situations, with different labor and other costs and differing methods of estimating costs. For example, with regard to water transport, the large motorized barge systems used in the U.S. are less sensitive to cooling-intake clogging and propeller fouling than are the small, individual, and relatively crude river steamers and small barges powered by outboard motors so commonly used for transporting goods in developing countries.

In developing countries considerable sums are spent for weed control. In most cases at least one half of the funds draw on scarce foreign exchange in paying for cutting apparatus and chemicals. Furthermore, needed labor for dam construction, flood control, fishing, and transportation is often idled as it must be used for weed harvesting or destruction as the control programs are carried out. The uranium and copper mining interests in the Congo Republic are known to have spent millions of dollars in this field. Egypt and the Sudan each spend about $1.5 million annually on control programs.

In the Sudan, an initial hyacinth control program involving technical advice, organization building, appropriate equipment and supplies, and control operations was supported by aid from 1960 to 1964. At the conclusion of the project, weed control activities employed 73 river craft of all types, 28 vehicles, 5 planes, 500 full-time employees and 500 seasonal laborers. Control was effected largely by 2,4-dichlorophenoxy (2,4-D) herbicide deployed from boats, land-based spray vehicles, and man-carried sprayers, as well as from aircraft under favorable weather conditions.^1,2,3,4,5

Country Specific Situations

All available reports agree that aquatic weeds present “serious economic problems” for developing countries and that these problems will increase unless major control measures are undertaken. An attempt has been made to translate the weed-menace assessments into very broad and quasispeculative dollar-equivalent losses. Several developing countries were selected as reasonably representative of those suffering economic losses which seem to have a measurable impact upon their economies. Principal attention is directed to losses due to constraints on transportation and fishing which are the easiest aspects to address in a quantitative manner.

Zambia

The inadequate road and railroad network of this landlocked country forces dependence on short-haul water transportation on the Zambesi, Kaufue, Luangiva, and Chambesi Rivers and Lakes Tanganyika and Kariba for internal commerce. The presence of rapids and varying seasonal depths of water inhibit long-haul river transport although logs and other freight are transported on the Zambesi above the falls at Livingstone. Trade with Rhodesia across Lake Kariba is limited. For at least 8 months of the year, these bodies of water are infested to some extent with aquatic weeds restricting waterborne transportation.

The effect on internal commerce is significant. Considering agriculture, forestry, and fishing only, a 2 to 3% impact due to blockages of waterways and fishing areas means an internal loss of commerce of several million dollars since these sectors account for more than $75 million of the country’s total commerce. Weed-clearance schemes, including reliance on imported equipment and materials, add another $750,000 to $1 million in costs annually. In addition, schistosomiasis has shown a 10% increase from 1965 to 1969, which may be related to the presence of aquatic weeds.

Thailand

The lower Mekong River Basin, as well as other riverine regions in Thailand, with their reservoirs, ponds, inlets, and channels, is infested with hyacinth, water lettuce, and water fern.

Very roughly, about 30%...

Table of contents

• Cover
• Title Page
• Copyright Page
• Table of Contents
• PART I: SPECIAL STUDIES FOR MANAGEMENT OF RECREATION WATERS
• PART II: SPECIAL STUDIES IN SMALL SCALE RECREATION WATER AREAS
• PART III: SPECIAL STUDIES IN LARGE SCALE RECREATION WATER AREAS
• PART IV: RESEARCH AND DEVELOPMENT STUDIES FOR CONTROL OF EURASIAN WATERMELFOIL
• APPENDIXES
• Glossary of Biolimnological Terms
• INDEX