soluble solids (sucrose). We evaluated a total of 2,400 

 apples from the 48 blocks. 



There were significant differences among the three 

 planting densities for weight. Apples in dwarf trees 

 planted at high densities produced larger apples on 

 average (145 g) (Table 1) than fioiit in the low-density 

 plantings (126 g), but medium density plantings (130 

 g) produced fruit which were not statistically different 

 from those from either high or low planting densities. 

 Planting density did not affect soluble solids, red color, 

 or flesh firmness. Relative to EPM level, fruit pro- 

 duced under bio-intensivc 'third-level-IPM' were less 

 red (62%) than fruit in first-level blocks (65%), but 

 no differences existed for fruit weight, soluble solids, 

 or flesh firmness. 



Just before commercial harvest, yield and crop 

 density was estimated. At the comers and centers of 

 each block, the total number of apples on and under 

 the trees were counted. Also, 20 trees from each block 

 (100% more than in 1997) were selected randomly and 

 the circumference of a single representative limb, at 

 the narrowest point before branching, was measured. 

 All fruit from the point of measure to the end of the 

 terminals (including subsequent branching) were 

 counted. 



according to third-level IPM strategies, and the other 

 was managed with traditional first-level IPM strate- 

 gies. 



What were the bio-intensive methods employed in 

 our third-level blocks'? Summer diseases were man- 

 aged with a fungicide-reduction plan tailor-made for 

 each block according to risk assessment. A flyspeck 

 prediction model was developed with these results, and 

 with continued environmental monitoring we hope to 

 refine our understanding of orchard disease ecology. 

 Traps that attract plum curculio visually and 

 olfactorally were developed to monitor and manage 

 this most challenging pest. Beneficial predatory mites 

 were seeded into third level blocks to manage pest 

 mites. Traps and products to manage the apple mag- 

 got with little or no insecticide are being refined each 

 year. 



Samples of 50 apples (150% more than in the 1997 

 evaluation) were selected for fruit quality evaluations 

 from a larger sample of 200 fruit that were evaluated 

 for pest incidence in each block at harvest. The 50 

 fruit were weighed, evaluated for percentage of red 

 (scale 0-100%), assessed for firmness, and tested for 



Table 3. Estimated yield of apples trees at 

 different planting densities and managed with 

 different IPM levels, 1999. 



Means within each column and treatment type not 

 followed by the same letter are significantly 

 differentatoddsof 19 to 1. 



Fruit Notes, Volume 64 (Number 4), Fall, 1999 



