ANNUAL REPORT OF THE COOPERATIVE REGIONAL RESEARCH PROJECT
Supported by Allotments of the Regional Research Fund
Hatch Act, as Amended August 11, 1995
January 1 to December 31, 2000
Project: NC-140 Rootstock and Interstem Effects on Pome and Stone Fruit Trees
(Revised October 1, 1997)
COOPERATING AGENCIES AND PRINCIPAL REPRESENTATIVES:
Station |
Cooperator |
Station |
Cooperator |
Station |
Cooperator |
AR |
C. Rom |
MN |
E. Hoover |
VT |
E. Garcia |
CA |
S. Johnson |
MO |
M. Warmund |
VA |
J. Barden |
CO |
A. Gaus |
NE |
W. Gustafson |
WA |
B. Barritt |
GA |
K. Taylor |
NJ |
W. Cowgill |
WV |
R. Bell |
IL |
M. Kushad |
NY |
T. Robinson |
WI |
T. Roper |
IN |
P. Hirst |
NC |
M. Parker |
||
IA |
P. Domoto |
OH |
D. Ferree |
Canada |
|
KS |
A. Erb |
OR |
E. Mielke |
BC |
F. Kappel |
KY |
G. Brown |
PA |
G. Green |
NB |
J. Prive |
ME |
J. Schupp |
SC |
G. Reighard |
NS |
C. Embree |
MA |
W. Autio |
SD |
A. Fennell |
ON |
J. Cline |
MD |
C. Walsh |
TN |
C. Mullins |
QU |
R. Granger |
MI |
R. Perry |
UT |
J.L. Anderson |
Mexico |
R.P. Quesada |
Administrative Advisor: I. Gray (MI-AES)
CSREES Representative: C. Stushnoff (CO-AES)
PROGRESS OF THE WORK AND PRINCIPAL ACCOMPLISHMENTS
Uniform rootstock and training system trials (Objective 1) are planned and coordinated by the technical committees at multiple sites for ten-year periods. Publications are prepared following the fifth and tenth years. Other objectives are researched at one or more locations.
Objective 1: Evaluate the performance of pome and stone fruit rootstocks in various environments under different management regimes
1988 Pear Rootstock Trial: Anita Azarenko
This trial is completed and a manuscript will be submitted for publication in 2001. A brief report was presented at an international meeting in Italy in the summer of 2000.
1990 Plum Rootstock Trial: Bob Anderson
This trial is completed and a manuscript is being prepared.
1990 Gala Apple Rootstock Trial: Rich Marini
This trial was terminated in 1999 and the first draft of a manuscript was passed out at the meeting to the 8 cooperating states. The final version of the manuscript will be submitted for publication in early 2001.
1990 Systems Trial: Rich Marini
Data collected from 8 locations showed slender spindle to be the most productive overall, but fruit was poorly colored. Vertical axe was intermediate in productivity with M.9 the best rootstock for this system. The central leaders system on M.26 or Mark was least productive because it took a longer time to fill in the space. This trial was completed in 1999 and a manuscript was distributed at the meeting. It will be submitted for publication in early 2001.
1990 Apple Cultivar/Rootstock Trial: Wes Autio
This trial was terminated in 1999 and a manuscript on overall results was distributed at the meeting. Three additional papers are being prepared on winter damage/blackheart injury, accessory cultivars, and spur quality/morphological differences. The main paper will be submitted for publication by March 1, 2001.
1992-1993 Liberty/CG Rootstock Trial: Terence Robinson
The 1992 planting will be discontinued following the 2000 season and the 1993 planting following the 2001 season. Data are currently being compiled for a 5-year summary of this trial.
1994 Gala Semi-Dwarf Apple Rootstock Trial: Rich Marini
A 5-year report was published in 2000. Tree survival has been good in this trial, although G.30 has been variable. At some sites, all trees have been lost. At others, all have survived. Alternate bearing is a problem at some sites.
1994 Gala Dwarf Apple Rootstock Trial: Rich Marini
A 5-year report was published in 2000. Survival has been good at most of the 25 locations. Biennial bearing is a problem at some sites. The various M.9 clones show some consistent differences. At the 11 sites that have Fleuren 56, it tends to be the smallest clone. NAKBT 337 is also small and Pajam 2 is larger.
1994 Peach Rootstock Trial: Greg Reighard
A 5-year report was reported at an international meeting in New Zealand and will be published in Acta Horticulturae. A more complete report will be submitted to the Journal of the American Pomological Society in 2001. Trees have survived well and the rootstocks have generally performed similarly to each other. Therefore, this planting may not be continued for the full 10 years.
1998 Cherry Rootstock Trial: Frank Kappel
Tree losses are high in the West with Bing as the scion. Largest trees are on Gisela 6 and Giessen 318-17. Serious problems with Pseudomonas in New York and bacterial canker in South Carolina. There are fruit size differences related to tree size. Mahaleb is the largest tree and has the smallest fruit size. W53 has good fruit size, yield and sugar levels. Preliminary summaries will be presented at the international cherry symposium in June 2001.
1998 G.16 Rootstock Trial: Terence Robinson
Flowers were removed in 1999, but trees will be allowed to crop in 2000. G.16 are larger than M.9 with both Gala and Jonagold as scions. G.16 is precocious, productive and fireblight resistant, but very sensitive to latent viruses. Year 4 (2001) should be a good crop year. Trees will be thinned to a moderate crop load. If trees are not vigorous, all fruit will be removed.
1999 Apple Rootstock Trial: Wes Autio
Data are still being collected and compiled for both 1999 and 2000.
Objective 2. To assess and improve asexual techniques of pome and stone fruit rootstocks.
Two states are working on techniques for the improved propagation of apple (NY) and pear (OR) rootstocks.
Objective 3. To improve the ability to identify pome and stone fruit rootstocks through morphological, biochemical and genetic differences
Efforts are continuing to confirm the identity of Cornell-Geneva series rootstocks around the world through DNA testing (NY).
Objective 4. To develop new and better pome and stone fruit rootstocks through breeding and genetic engineering
AR – An ongoing breeding program for both apple and peach rootstocks is being carried out in Arkansas. Twelve apple selections were budded to Smoothee Golden Delicious in 1999 and will be planted in a replicated trial in 2001. For peach rootstocks, 24 in 1997 and another 20 in 2000 were selected for further evaluations.
CA – A peach rootstock breeding program is being conducted to combine disease resistance with dwarfism and other desirable horticultural traits.
NY – The apple rootstock breeding program at Cornell-Geneva will be releasing 4 new rootstocks over the next 3 years. In additional, new rootstocks from around the world are being gathered. In 1999, 16 rootstocks from 3 European breeding programs were established.
OH – Five selections of the Morioka series of rootstocks have been obtained and are being cloned for further evaluations.
Ontario – The Vineland series of apple rootstocks together with several standard are being evaluated for fire blight resistance. The results indicate that wide differences in rootstock susceptibility exist.
Objective 5: To determine biotic and abiotic stress tolerance of pome and stone fruit trees in relation to new and existing rootstocks.
New Brunswick – The Cornell-Geneva apple rootstocks are being screened for cold hardiness.
NY – The Cornell-Geneva rootstocks, as well as many others from around the world, are being screened for tolerance to such biotic and abiotic factors as replant disease, late winter cold temperatures, Phytophthora root rots and fire blight. Three-year-old Gala trees on various rootstocks were inoculated with fireblight in 1999. During 2000, most of the standard rootstocks died, whereas most of the Cornell-Geneva rootstocks have survived so far.
OH – A visiting scientist from China is studying the interaction of soil compaction and water stress on apple physiology using M.9 EMLA as the rootstock.
Ontario – Studies are continuing the evaluate the fireblight sensitivity and cold hardiness of the Vineland series of apple rootstocks compared to several known standard rootstocks.
UT – Field studies have been conducted to evaluate fireblight sensitivity and bud union breakage under high winds of Gala apples on different rootstocks. Experiments on cherry bud cold hardiness in the fall have shown that Colt rootstock are 2 to 4 degrees C less hardy than buds on trees growing on GM.61.1, MXM.2, Mahaleb, Mazzard and Gi.148.1.
USEFULNESS OF FINDINGS AND IMPACT OF COOPERATIVE RESEARCH PROJECT
Uniform trials continue to suggest superior rootstock selections in an unbiased manner. Nearly all states indicate the importance of the results from these trials as the primary source of information for recommendations made by research and extension personnel. Fire blight continues to be a major limiting factor for apple rootstock selection and several sites are actively involved in screening and other studies to determine sensitivity and reduce tree losses. State surveys of tree planting indicate a dramatic shift to trees on more dwarfing rootstocks in recent years. Growers and industry recognize the importance of unbiased information from broad uniform trials and more than $1,000,000 is given to support these trials and related rootstock projects.
WORK PLANNED FOR NEXT YEAR
The current project (renewed October 1997) will continue through September 2002. A rewrite committee was formed to prepare a draft for the next annual meeting. Existing trials will be maintained following the protocols developed by the respective technical committees. Current (and supplemental) data will continue to be collected and summarized by the planting coordinator, who will prepare the five- and ten-year reports for publication. Individual state project leaders will, wherever possible, expand the data collection on a particular planting beyond that of the uniform data set so as to gain further information on rootstock performance, or how the rootstocks respond to training and local conditions. As new, not as yet commercially available, rootstocks are wanted for the trials, plantings must be planned three to five years prior to the actual planting being made. The following new trials are in the planning stage:
2001/2002 Peach Rootstock Trial: Greg Reighard
This trial had problems with poor performance of some rootstocks and budded trees in the nursery. The decision was made to salvage the rootstocks that had reasonable bud take and put out a limited trial in 2001. The remaining rootstocks will be propagated again for the 2002 planting.
2002/2003 Pear Rootstock Trial: Gene Mielke
Nine sites have been identified for planting this trial. In 2002 there will be 9 stocks and in 2003 another 12-14 rootstocks will be planted.
2003 Apple Rootstock Trial: Terence Robinson
This trial was originally planned for 2002 but there was very poor take of some of the rootstocks in the nursery. The plan now is to delay until 2003 and have a slightly larger trial. There are over 40 rootstocks on the list but this will be reduced by factors such as availability, fire blight resistance, etc.
2004 Cherry Rootstock Trial: Frank Kappel
This planting has also been delayed a year because of problems with obtaining the desired rootstock and getting them through virus sensitivity testing in time for planting. There are about 30 stocks on the list from Europe, Russia and California.
PUBLICATIONS
Refereed (full length)
Choi, Cheol, K. G. Livermore and R. L. Andersen. 2000. Sweet cherry pollinations: Recommendation based on compatibility groups and bloom time. J. Amer. Pomol. Soc. 54(3):148-152.
Embree, C. G., E. N. Estabrooks, and H.-Y. Ju. 2000. Blackheart in a Tender Apple Cultivar is Not Influenced by Using a Hardy Frame. HortScience 35(4):604-607.
Marini, R. P., J. L. Anderson, B. H. Barritt, G. R. Brown, J. Cline, W. P. Cowgill, Jr., P. A. Domoto, D. C. Ferree, J. Garner, G. M. Greene, C. Hampson, P. Hirst, M. M. Kushad, E. Mielke, C. A. Mullins, M. Parker, R. L. Perry, J. P. Privé, G. L. Reighard, T. Robinson, C. R. Rom, T. Roper, J. R. Schupp, E. Stover, and R. Unrath. 2000. Performance of ‘Gala’ apple on four semi-dwarf rootstocks: a five-year summary of the 1994 NC-140 semi-dwarf rootstock trial. J. Amer. Pomol. Soc. 54(2):84-91.
Marini, R. P. J. L. Anderson, W. R. Autio, B. H. Barritt, G. R. Brown, J. A. Cline, W. P. Cowgill, Jr., R. M. Crassweller, P. A. Domoto, D. C. Ferree, J. Garner, A. Gaus, G. M. Greene, C. Hampson, P. Hirst, M. M. Kushad, E. Mielke, C. A. Mullins, M. Parker, R. L. Perry, J. P. Privé, G. L. Reighard, T. Robinson, C. R. Rom, T. Roper, J. R. Schupp, E. Stover, and R. Unrath. 2000. Performance of ‘Gala’ apple on 18 dwarf rootstocks: five-year summary of the 1994 NC-140 dwarf rootstock trial. J. Amer. Pomol. Soc. 54(2):92-107.
Perry, R., G. Reighard, D. Ferree, J. Barden, T. Beckman, G. Brown, J. Cummins, E. Durner, G. Greene, S. Johnson, R. Layne, F. Morrison, S. Myers, W. R. Okie, C. Rom, R. Rom, B. Taylor, D. Walker, M. Warmund and K. Yu. 2000. Performance of the 1984 NC-140 Cooperative Peach Rootstock Planting. J. Amer. Pomol. Soc. Vol. 54(1):6-10.
Refereed (in press)
Al-Hinai, Y. K. and T. R. Roper. 2000. Temporal Effects of Chemical Weed Control on Tart Cherry Tree Growth, Yield and Leaf Nitrogen Concentration. HortScience (in press).
Warmund, M. 2000. Early performance of ‘Red Fuji’ on M.9 clones and other dwarfing rootstocks. J. Amer. Pomol. Soc. (in press).
Refereed (abstracts)
Autio, W. R. 2000. Rootstock and scion interact to affect apple tree performance: Results from a 10-year trial by the NC-140 Technical Committee. HortScience 35:499-500 (abstract).
Non-Refereed (Proceedings)
Aldwinckle, H., T. Robinson, J. Norelli, T. Momol, and M.V.B. Reddy. 2000. Controlling shoot blight with Apogee. New York Fruit Quarterly 8(l):19-22.
Aldwinckle, H., J. Norelli, S. Brown, T. Robinson, E. Borejsza‑Wysocka, H. Gustafson, J.P. Reynoird, and M.V.B. Reddy. 2000. Genetic engineering of apple for resistance to fire blight. New York Fruit Quarterly 8(l):24-26.
Autio, W. R., J. L. Anderson, J. A. Barden, G. R. Brown, R. M. Crassweller, P. A. Domoto, A. Erb, D. C. Ferree, A. Gaus, P. Hirst, C. A. Mullins and J. R. Schupp. 2000. Rootstock and scion interact to affect apple tree performance results from the 1990 NC-140 cultivar/rootstock trial. Acta Horticulturae.
Autio, W. R. 1999. Ottawa 3: A summary of twenty years of trial. Fruit Notes 64(2):12-13.
Azarenko, Anita, Robert Anderson, Gerald Brown, Charlie Embree, David Ferree, Alan Gaus, David Hunter, Frank Kappel, Del Ketchie, Eugene Mielke, Rocy Renquist, and David Sugar. 2000. Final evaluation of the NC-140 national rootstock trial. ISHS 8th Intern. Pear Symp., p. 90 (Abstract).
Barritt, B. H. 2000. Selecting an orchard system for apples. Compact Fruit Tree 33(3):89-92.
Barritt, B. H. 2000. The HYTEC (Hybrid Tree Cone) orchard system for apples. Acta Hort. in press.
Brown, Gerald R. and Dwight Wolfe. 2000. Rootstock and Interstem Effects on Pome and Stone Fruit Trees. Fruit and Vegetable Crop Research Report – 1999. University of Kentucky publication PR-423:14-18.
Brown, Gerald R. and Dwight Wolfe. 2000. Optimal Training of Apple Trees for High-density Plantings. Fruit and Vegetable Crop Research Report – 199. University of Kentucky publication PR-423:19-20.
Hirst, P. M., R. P. Marini, J. L. Anderson, W. R. Autio, J. A. Barden, B. H. Barritt, G. R. Brown, J. A. Cline, W. P. Cowgill, R. M. Crassweller, P. A. Domoto, D. C. Ferree, J. M. Garner, A. Gaus, G. M. Greene, C. R. Hampson, M. M. Kushad, E. Mielke, C. A. Mullins, M. L. Parker, R. L. Perry, J. P. Privé, G. L. Reighard, T. L. Robinson, C. R. Rom, T. Roper, J. R. Schupp, E. Stover, and C. R. Unrath. 2000. Early performance of ‘Gala’ on 18 dwarf and 4 semi-dwarf rootstocks growing at 24 sites in North America. Acta Hort., in press.
Hoying, S.A and T.L. Robinson. 2000. The orchard planting systems puzzle. Acta Hort. 513:257-260.
Hoying, S. A., T. L. Robinson and A. DeMarree. 2000. Production, fruit quality and labor requirements of five high-density apple orchard systems over 10 years. 7th International Symposium on Orchard and Plantation Systems. Program and Abstracts p. 35.
Johnson W.C., H. S. Aldwinckle, J. N. Cummins, P. L. Forsline, H. T. Holleran, J. J. Norelli, and T. L. Robinson. 2000. The USDA-ARS/Cornell University apple rootstock breeding and evaluation program. 7th International Symposium on Orchard and Plantation Systems. Program and Abstracts p. 3.
Johnson W.C., J. N. Cummins, H. T. Holleran, S. A. Hoying and T. L. Robinson. 2000. Orchard trial performance of elite Geneva series rootstocks. 7th International Symposium on Orchard and Plantation Systems. Program and Abstracts p. 7.
Kushad, M. 2000. Marketing strategies for small produce farm: meeting the demands of the 21st century. Trans. Illinois State Hort. Soc. 133:32-34.
Kushad, M. 2000. Rootstocks for Illinois apple orchards. Trans. Illinois State Hort. Soc. 133:44-45.
Kushad, M. 2000. The vertical axe: a simple and easy way to manage training systems for apple. Trans. Illinois State Hort. Soc. 133:52-55.
Kalt, W. and M. Kushad. 2000. The role of oxidative stress and antioxidants in plant and human health: Introduction to the colloquium. Hort. Sci. 35:572.
Lakso, A. N, T. L. Robinson, M. C. Goffinet and M. D. White. 2000. Apple fruit growth responses to varying thinning methods and timing. 7th International Symposium on Orchard and Plantation Systems. Program and Abstracts p.75.
Mielke, Eugene A. 2000. D’Anjou and Bosc fruit quality as affected by rootstock and training system. ISHS 8th International Pear Symposium, p. 201 (Abstract).
Mielke, Eugene A. 2000. Effect of Chloropicrin as a soil fumigant. ISHS 8th International Pear Symposium, p. 232 (Abstract).
Mielke, Eugene A. and Laurel Smith. 2000. Effect of budding height on tree size and precocity. ISHS 8th International Pear Symposium, p. 112 (Abstract).
Mielke, Eugene A. and Laurel Smith. 2000. Evaluation of the Horner rootstocks. ISHS 8th International Pear Symposium, p. 91 (Abstract).
Mielke, Eugene A. and Janet Turner. 2000. Evaluation of pear interstems. ISHS 8th International Pear Symposium, p. 113 (Abstract).
Perry, R. L. 2000. The vertical axis system in North America. Acta Horticulturae 513:297-301.
Perry, R. L. and G. V. Byler. 2000. Performance of Liberty on 8 Semi-dwarfing Cornell-Geneva rootstocks. Proceedings of 129th Annual Michigan State Horticultural Society. 129:196-199.
Perry, R. L. and G. V. Byler. 2000. Performance of Liberty on 9 Dwarfing and Semi-dwarfing rootstocks in a 1992 NC-140 rootstock trial. Proceedings of 129th Annual Michigan State Horticultural Society. 129:200-203.
Perry, R. and G. V. Byler. 2000. Effects of 19 rootstocks on the performance of Imperial Gala grown in the “V” System. Acta Hort. ISHS 7th Orchard System Plantation Symposium, Jan 31-Feb 4, 2000, Nelson, NZ (In Press)
Privé, J.P., J. M. Caprio, H. A. Quamme, C. Embree, and D. Hebb. 2000. Weather conditions associated with apple production in the Annapolis Valley of Nova Scotia and the Okanagan Valley of British Columbia. Proceedings of the 11th Atlantic region hydrotechnical conference, Moncton, N.B. pp. 39.
Privé, J.P., M. I. N. Zhang, C. Embree, and D. Hebb. 2000. The influence of freeze-thaw cycling in cold hardiness studies on apple rootstocks. Acta Hort. (in press).
Reighard, G. L. and NC-140 Cooperators. 2000. Five-year performance of 19 peach rootstocks at 20 sites in North America. Acta Hort. (accepted).
Robinson T.L. 2000. Long‑term performance and economics of high-density apple orchard systems. 7th International Symposium on Orchard and Plantation Systems. Program and Abstracts, p. 33.
Robinson, T. L. 2000. V-shaped apple planting systems. Acta Hort. 513:337-347.
Robinson, T. L and S. A. Hoying. 2000. Lessons learned about tree support from the 1998 labor day storm. Compact Fruit Tree 33:12-18.
Robinson T. L. and J. A. Flore. 2000. The physiological basis of orchard systems. 7th International Symposium on Orchard and Plantation Systems. Program and Abstracts, p. 61.
Tuttle, A., D. Smith, J. Hall, M. Frank, D. Cooley, S. Wright, J. Black, S. Lavalle, and W. Autio. 1999. Effects of planting density and IPM level on apple fruit quality. Fruit Notes 64(2):6-7.
Tuttle, A., J. Smith, C. Bergweiler, D. McPadden, S. Christle, S. Wright, J. Black, and W. Autio. 1999. Effects of planting on density and IPM level on apple fruit quality and crop density, 1999 results. Fruit Notes 64(4):1-3.
Extension
Agnello, A. M., W. F. Wilcox, D. A. Rosenberger, T. L. Robinson, J. R. Schupp, P. D. Curtis, D. I. Breth, and S. A. Hoying. 2000. Pest management guidelines for commercial tree-fruit production 2000. Cornell University, Ithaca NY.
Clements, J. and W. Cowgill. July 2000. "Apple Crop Report from IDFTA" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 14 (4).
Clements, J. and W. Cowgill. July 2000. "Honeycrisp‑the Good, the Bad, & the Ugly" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 14 (5).
Clements, J. and W. Cowgill. April 2000. "Apogee®: New PGR for Growth Control" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 2 (3).
Compton, J. and W. Cowgill. "Understanding Water Hardness" Pennsylvania Fruit News, August 2000. Vol. 80. 8 (26).
Compton, J., M. Peters, W. Cowgill. September 2000. "Apple Maturity Update for North Jersey", Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 24 (3).
Compton, J. and W. Cowgill. September 2000. "North Jersey Tree Fruit Maturity Update", Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 3 (1).
Compton, J., W. Cowgill, M. Peters. September 2000. "North Jersey Apple Maturity Advances" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 22 (1).
Compton, J., W. Cowgill, M. Peters. August 2000. "Monitor Those Sugars" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 21 (3).
Compton, J. and W. Cowgill. May 2000. "Understanding Water Hardness" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5 No. 5 (5).
Compton, J., W. Cowgill, M. Peters. August 2000. "Stay In Tune With Apple Maturity" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 20 (l).
Compton, J. and W. Cowgill. August 2000. "North Jersey Apple Maturity Update" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 19 (5).
Compton, J. and W. Cowgill. April 2000. "Apogee® Benefits for Apple & Pear" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 3 (3).
Compton, J. and W. Cowgill. August 2000. "Stem-End Split and Internal Ring Crack of Gala and Fuji" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 18 (1).
Compton, J. and W. Cowgill. April 2000. "Helpful Equations for Calibrating Airblast Sprayers" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5, 2 (5).
Compton, J. and W. Cowgill. April 2000. "Helpful Equations for Calibrating Airblast Sprayers" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 6, 4 (1).
Cowgill, W. P., J. M. Compton, R. Best Sr., G. Donato, M. Maletta. 2000. "Procure® 50WS Evaluations in Apple", Rutgers University Field Study, Snyder Research and Extension Farm, Horticultural News, Vol. 80(3) 6-8, 22-25.
Cowgill, W., J. Clements, J. Compton. August 2000. "Painless and Efficient Apple Maturity Testing" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, August, 2000 Vol. 5. 19 (4).
Cowgill, W. and J. Compton. August 2000. "US Apple Crop Forecast" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 21 (4).
Cowgill, W. and J. Compton. August 2000. "Sweet Cherry and Bacterial Canker" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 17 (7).
Cowgill, W. and J. Compton. July 2000. "Managing Apple and Pear Harvest with ReTain® Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 16 (1).
Cowgill, W. and J. Clements. July 2000. "IDFTA Summer Tour" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 16 (1).
Cowgill, W. May 2000. "Chemical Thinning and Return Bloom on 'Fuji' Apple" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 9 (4).
Cowgill, W. and J. Compton. May 2000. "Techniques to Enhance Return Bloom in Apple" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 8 (2).
Cowgill, W. May 2000. "Still Time To Do Apple Thinning" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 7 (6).
Cowgill, W., M. Peters, J. Compton. May 2000. "North Jersey Crop Update" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 5 (5).
Cowgill, W., J. Compton, R. Belding. May 2000. "Apogee® Plant Growth Regulator Receives Registration" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 5 (6).
Cowgill, W. April, 2000. "Thoughts on Apple Thinning, Part 11" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 4 (4).
Cowgill, W. and J. Compton. April 2000. "Apple Foliar Nutrient Suggestions for 2000" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 3 (3).
Cowgill, W. April 2000. "Thoughts on Apple Thinning, Part I", Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 3 (6).
Cowgill, W., M. Peters, J. Compton. April 2000. "Surprise Snowstorm and Freeze Hits North Jersey" Rutgers Cooperative Extension Plant & Pest Advisory Newsletter, Fruit Edition, Vol. 5. 2 (1).
Crassweller, R. M. and D. E. Smith. 2000. Apple training system trials – 1999. PA Fruit News 80(4):18, 20-24.
Crassweller, R. M. and C. Backman. 2000. Pruning and training apple trees to the French Axe system. (slide set and web slide at http://tfpg.cas.psu.edu/french_axe/slide1.htm)
Crassweller, R. M. 2000. Apple rootstocks in Pennsylvania Tree Fruit Production Guide 2000-01. J. W. Travis (coordinator) pp. 29-31. The Pennsylvania State University.
Domoto, P. 2000. Progress report on the Iowa planting of the NC‑140 1990 regional apple cultivar by rootstock trial for 1999. Annual Fruit/Vegetable Progress Report 1999. ISU Ext., FG‑601:34-35. (Annual Fruit/Vegetable Progress Reports for 1997, 1998 and 1999 are available as pdf files at: http://www.hort.iastate.edu/pages/pubs/p_frame.html under "Extension".
Domoto, P. 2000. Progress report on the Iowa planting of the 1993 NC‑140 Cornell‑Geneva apple rootstock trial for 1999. Annual Fruit/Vegetable Progress Report 1999. ISU Ext., FG‑601:36-38. (Annual Fruit/Vegetable Progress Reports for 1997, 1998 and 1999 are available as pdf files at: http://www.hort.iastate.edu/pages/pubs/p_frame.html under "Extension".
Domoto, P. 2000. Progress report on the Iowa planting of the 1994 NC‑140 dwarf apple rootstock trial for 1999. Annual Fruit/Vegetable Progress Report 1999. ISU Ext., FG601:39-41.
(Annual Fruit/Vegetable Progress Reports for 1997, 1998 and 1999 are available as pdf files at: http://www.hort.iastate.edu/pages/pubs/p_frame.html under "Extension".
Domoto, P. 2000. Progress report on the Iowa planting of the 1994 NC-140 semi-dwarf apple rootstock trial for 1999. Annual Fruit/Vegetable Progress Report 1999. ISU Ext., FG601:42-43. (Annual Fruit/Vegetable Progress Reports for 1997, 1998 and 1999 are available as pdf files at: http://www.hort.iastate.edu/pages/pubs/p_frame.html under "Extension".
Domoto, P. 2000. Progress report on the ISU 1989 apple cultivar by rootstock trial for 1999. Annual Fruit/Vegetable Progress Report 1999. ISU Ext., FG‑601:44-46. (Annual Fruit/Vegetable Progress Reports for 1997, 1998 and 1999 are available as pdf files at: http://www.hort.iastate.edu/pages/pubs/p_frame.html under "Extension".
Domoto, P. 2000. Progress report on the ISU 1991 apple cultivar x interterm x rootstock trial for 1999. Annual Fruit/Vegetable Progress Report 1999. ISU Ext., FG-601:47-9. (Annual Fruit/Vegetable Progress Reports for 1997, 1998 and 1999 are available as pdf files at: http://www.hort.iastate.edu/pages/pubs/p_frame.html under "Extension".
Domoto, P. and Barb Smith. 2000. Progress report on the Western Iowa 1992 apple cultivar x rootstock trial for 1999. Annual Fruit/Vegetable Progress Report 1999, ISU Ext., FG601:80-81. (Annual Fruit/Vegetable Progress Reports for 1997, 1998 and 1999 are available as pdf files at: http://www.hort.iastate.edu/pages/pubs/p_frame.html under "Extension".
Greene II, G. M. and W. Kleiner. 2000. Influence of rootstocks on the growth, productivity, and longevity of apple trees. Penn Fruit News 80(2):39-42.
Perry, R. 2000. Planting fruit trees in 2000. CAT, Fruit Ed. MSU Extension, 15(1):2-4.
Perry, R., J. Hull and J. Clements. 2000. Internet site helps with apple scion/rootstock selection and planning. CAT, Fruit Ed. MSU Extension, 15(1):4.
Perry, R. 2000. Belgium produces more than waffles and chocolates. CAT, Fruit Ed. MSU Extension, 15(2):1-2.
Perry, R. 2000. Keys to maintaining productive vertical axe trees. CAT, Fruit Ed. MSU Extension, 15(2):2-3.
Perry, R. 2000. Brief comments about new apple stocks. CAT, Fruit Ed. MSU Extension, 15(2):5-7.
Rom, C. R. 2000. Peach Rootstocks and Orchard Systems for the Arkansas-Oklahoma Region. Arkansas-Oklahoma Horticulture Industries Show. p. 9-16.
Newspapers & Magazines
Belding, R. D., W. P. Cowgill Jr., J. L. Frecon, G. C. Hamilton, J. R. Heckman, L. S. Katz, N. Lalancette, B. A. Majek, D. Polk, P. W. Shearer, W. H. Tietjen. 2000. "New Jersey Commercial Tree Fruit Production Guide." Rutgers Cooperative Extension Bulletin E003L, 142 total pages, pp. 11, 12, 15, 18, 67-69, 77-89, 118, 130.
Cowgill, W. and J. Clements. April 2000. "The International Dwarf Fruit Tree Association Goes Down Under". Western Fruit Grower, Fruits, Grapes, Nuts. Vol. 120. 4
Perry, R. 2000. Training sweet cherries. American Fruit Grower. Vol. 120 (4):34-38.
Perry, R. 2000. Guidelines for establishing sweet cherry trees on Gisela rootstocks. The Fruit Growers News. 39(5):20.
Perry, R. 2000. The keys to maintaining productive Vertical Axe trees. The Fruit Growers News. 39(5):21.