of Concord grapes related to mechanical harvesting and han- 

 dling. Transactions ASAE. 14:373-376. 



Tennes. B. R. J. H. Levin and B. A. Stout. 1964. Sweet cher- 

 ry properties useful in harvesting and handling equipment de- 

 sign. Transactions ASAE. 12:710-714. 



Control of Soil Structure 



The possibility of managing intensively cultivat- 

 ed soils by application of polymer chemistry was 

 demonstrated during the 1950's. A wider range of 

 substances has become available, and there are 

 now available materials that can stimulate seed- 

 ling growth, reduce evaporative losses from soil, 

 and ameliorate the severity of diseases. The po- 

 tential exists for providing nitrogen and phosphor- 

 us bound to these polymers in time-release mech- 

 anisms that will improve their efficiency and 

 reduce their propensity to be lost by leaching and 

 surface erosion so as to cause eutrophication of 

 nearby streams and lakes. 



Paris, D. F., G. Chester and O. N. Allen. 1966. Dynamics of 

 Soil Aggregation. Advances in Agronomy 18:107-160. 



Water Quality 



Water standards identified in Section 208 of 

 Public Law 92-500 require that increased empha- 

 sis be given to the environmental aspects of 

 chemical behavior. Basic research on erosion, 

 hydrology, sedimentation, and environmental 

 behavior of agricultural chemicals and sediments 

 has generated a large volume of data in recent 

 years. These data are now being brought together 

 and structured into mathematical models for pre- 

 dicting environmental transport of agricultural 

 chemicals (pesticides and fertilizers) and sedi- 

 ments from agricultural lands, mine spoils, and 

 other disturbed areas. Such models have potential 

 applications for improving production and man- 

 agement practices for crops, as well as for meet- 

 ing the mandates of Public Law 92-500. 



Committee of ARS scientists. B. A. Stewart, Coord. 1976. 

 Control of water pollution from cropland. Vols. I and 11. 

 ARS-H-.S-I and ARS-H-5-2. 298 p. 



Epstein, E.. G. B. Willson, W. D. Burge. D. C. Mullen, and 

 N. K. Enkiri. 1976. A forced aeration system for composting 

 wastewater sludge. J. Water Pollut. Control Fed. 48:688-694. 



Fouss. J. L. and R. C. Reeve. 1968. The laser in construction: 

 "Lilc-I,inc" guides a pipeline. Laser Focus 4:31-34. 



Frere. M. H., C. A. Onstad. and H. N. Holtan. I97.S. 

 ACTMO, An agricultural chemical transport model. U.S. 

 Dept. Agr. ARS-H-3. 54 p 



Hutchison. G. L. and F. G. Viets, Jr. 1969. Nitrogen enrich- 

 ment of surface water by absorption of ammonia volatilized 

 from cattle feedlots. Science 166:514- .'^l.'i. 



Jackson. R. D.. R. J. Reginato. B. A. Kimball, and F. S. Na- 



18 AGRICULTURE 



kayama. 1974. Diurnal soil-water evaporation: Comparison of 

 measured and calculated soil-water fluxes. Soil Sci. Soc. 

 Amer. Proc. 38:861-866. 



Jensen, M. E., J. L. Wright, and B. J. Pratt. 1971. Estimating 

 soil moisture depletion from climate, crop and soil data. 

 Amer. Soc. Agr. Engin. Trans. 14:954-959. 



Kibler. D. F. and D. A. Woolhiser. 1970. The kinematic cas- 

 cade as a hydrologic model. Colo. State U. Hydrol Paper No. 

 39. 27 p. 



Meyer. L. D., W. H. Wischmeier, and W. H. Daniel. 1971. 

 Erosion, runoff, and revegetation of denuded construction 

 sites. Amer. Soc. Agr Engin. Trans. 14:138-141. 



Plimmer. J. R. and B. E. Hummer. 1969. Photolysis of amiben 

 (3-aniino-2.5-dichlorobenzoic acid) and its methyl ester. 

 J. Agr. FoodChem. 17:83. 



Plimmer. J. R., P. C. Kearney, D. D. Kaufman, and F. S. 

 Guardia. 1967. Amitrole decomposition by free radical-gener- 

 ating systems and by soils. J. Agr. Food Chem. 15:996. 



Rawlins, S. L. and P. A. C. Raats. 1975. Prospects for high- 

 frequency irrigation. Science 188:604-610. 



van Schilfgaarde. J., L. Bernstein, J. D. Rhoades, and S. 1-. 

 Rawlins. 1974. Irrigation management for salt control. Amer. 

 Soc. Civ. Engin.. Irrig. & Drain. Div.J. 100:321-338. 



Singh, V. P. and D. A. Woolhiser. 1976. A nonlinear kinematic 

 wave model for watershed surface runoff. J. Hydrol. 31:221- 

 243. 



Smith, R. E. and D. A. Woolhiser. 1971. Mathematical simula- 

 tion of infiltrating watersheds. Colo. State U. Hydrol Paper 



No. 47. 44 p. 



Wischmeier. W. H and J. V. Mannering. 1969. Relation of 

 soil properties to its erodibility. Soil Sci. Soc. Amer. Proc. 

 33:131-137. 



Woolhiser, D. A., R. E. Smith, and C. A. Hanson. 1970. 

 Evapotranspiration components of watershed models for the 

 Great Plains. Evapotranspiration in the Great Plains. Agr. 

 Council Pub., pp. 1 1 1-1.36. 



Systemic Insecticides 



Recent innovations in molecular design of sys- 

 temic insecticides have produced phloem mobile 

 systemics (PMS) that pass through plant cell 

 membranes, translocate with sugars, and concen- 

 trate in living phloem tissue. Because many forest 

 insects feed on rapidly growing phloem tissue 

 where the PMS is concentrated, much-reduced 

 dosages of toxicants are needed for effective pest 

 control. The necessary chemical structure for 

 phloem mobility has been determined, and the 

 practical effectiveness of one PMS has been dem- 

 onstrated experimentally against the western 

 spruce budworm. The PMS principle lends itself 

 to development of chemicals that are innocuous 

 until converted by plants into toxicants and is 

 adaptable to other pesticides, e.g., fungicides, 

 herbicides, animal repellents. These chemicals 

 ofTer promise of greater specificity toward target 

 pests and reduced hazards to humans and other 



