Crop Protection 22 (2003) 1149–1156 Economic implications of a virus prevention program in deciduous tree fruits in the US Tiziano Cembali a, *, Raymond J. Folwell a , Philip Wandschneider a , Kenneth C. Eastwell b , William E. Howell b a Department of Agricultural and Resource Economics, Washington State University, P.O. Box 646210, Pullman, WA 99164, USA b Irrigated Agricultural Research & Extension Center, Washington State University, 24106 N. Bunn Road, Prosser, WA 99350, USA Received 17 September 2002; received in revised form 13 June 2003; accepted 16 June 2003 Abstract Viral diseases in fruit trees present a potential danger that could injure the fruit industry, the planting stock industry (nurseries), and consumers in the United States and abroad. Currently, the US has a virus protection program (VPP) that serves to minimize the spread of viral diseases. This paper reports research estimating the economic consequences of the loss of the program on nurseries, growers and consumers. The potential economic losses are a measure of the value of the existing program. The paper focuses on apples, sweet cherries, and Clingstone peaches. The effects of a loss of a VPP on nurseries would include direct and indirect losses from viral diseases in the form of lower quantity and quality of planting stocks. Fruit growers would be affected by reduced plant growth and fruit yield. Consumers would be affected by higher prices and reduced quantity of fruit. We measured benefits of the virus prevention program as changes in consumer and producer surpluses. Empirical estimates were made using the method of avoided losses. Benefit estimates to three economic sectors—nurseries (avoided change in producer surplus), producers (avoided change in consumer and producer surpluses), and consumers (avoided change in consumer surplus)— were calculated. Total benefits for all three sectors were approximately $227.4 million a year, or more than 420 times the cost of the program. Our analysis utilizes a method that might be used to evaluate other programs that prevent the introduction of plant diseases. r 2003 Elsevier Ltd. All rights reserved. Keywords: Virus; Losses; Economic evaluation; Fruit growers; Nursery; Consumers 1. Introduction Viral diseases cause economic losses through lower yields and reduced quality of plant products. Viral diseases in perennial crop plants are more dangerous than in annual crops. Viruses can remain latent, spreading through an orchard and inflicting damage, sometimes without the growers’ knowledge. Latent infestations can produce small to moderate losses in fruit production (Agrios, 1997). Often growers can maintain the productivity of diseased orchards at a profitable level by cutting infected parts and replacing dead trees to control the spread of the virus. Sometimes, however, losses are severe, and an acute viral infection can require tree removal. Between orchards, viral diseases spread thorough vegetative propagation. In tree fruit husbandry two methods are used to control viral diseases: adoption of virus-free propagation materials and eradication of contaminated trees. The literature reports different types of damages to fruit products. Damages include: unmarketable fruits (Reeves and Cheney, 1962), substantial reduction in yields (Tables 1 and 2), and extensive tree death (Stouffer and Smith, 1971). However, the damage caused may be less dramatic and still affect profits— reduced growth, lower yields or other adverse pheno- mena may exist at low levels but remain unobserved by growers. Overall, viral infections have a greater effect on crop yields and fruit quality (deformation, and loss of flavors) ARTICLE IN PRESS *Corresponding author. Tel.: +1-505-335-5555; fax: +1-505-335-1173. E-mail address: tiziano@wsu.edu (T. Cembali). 0261-2194/$-see front matter r 2003 Elsevier Ltd. All rights reserved. doi:10.1016/S0261-2194(03)00156-X