| Year | Location | Local Chair | Atnd | Theme |
| 1924 | Stamford, CT, US | | 33 | |
| 1925 | Boston, MA, US | | 42 | |
| 1926 | Philadelphia, PA, US | AFW Vick | 70 | |
| 1928 | Washington, DC | F.L. Mulford | 60 | |
| 1929 | Brooklyn, NY, US | H.H. Graves | 115 | |
| 1930 | Cleveland, OH, US | Chas. F. Irish | 167 | |
| 1931 | Yonkers, NY, US | NG Armstrong | 282 | |
| 1932 | Rochester, NY, US | L.C. Allyn | 77 | |
| 1933 | New York, NY, US | H Vaughn-Earnes | 185 | |
| 1934 | Pittsburgh, PA, US | R. M. Weakley | 128 | |
| 1935 | Phil., PA, US | J.G. Heinicke | 261 | |
| 1936 | Boston, MA, US | H.L. Frost | 419 | |
| 1937 | Baltimore, MD, US | H.S. Clopper | 391 | |
| 1938 | St. Louis, MO, US | V.I. Shield | 274 | |
| 1939 | New York, NY, US | N. Armstrong | 447 | |
| 1940 | Detroit, MI, US | J.M. Bennett | 392 | |
| 1941 | Washington, DC | H VanWormer | 379 | |
| 1942 | Chicago, IL, US | A.E. Price | 245 | |
| 1943 | | | | |
| 1944 | Pittsburgh, PA, US | W. P. Morrow | 185 | |
| 1945 | | | | |
| 1946 | Boston, MA, US | E.W. Kiggins | 551 | |
| 1947 | Cleveland, OH, US | Chas. F. Irish | 645 | |
| 1948 | Milwaukee, WI, US | C.L. Wachtel | 541 | |
| 1949 | Baltimore, MD, US | H.S. Clopper | 490 | |
| 1950 | Syracuse, NY, US | W.R. Herrmann | 493 | |
| 1951 | Cincinnati, OH, US | E.W. Sanford | 578 | |
| 1952 | Boston, MA, US | K.F. Amalia | 601 | |
| 1953 | Chicago, IL, US | N.B. Wysong | 597 | |
| 1954 | Atlatnic City, NJ, US | Winston Parker | 624 | |
| 1955 | Santa Barbara, CA, US | Van Rensselaer | 587 | |
| 1956 | Toronto, ON, Canada | F.E. Martin | 664 | |
| 1957 | Philadelphia, PA, US | J.C. Kenealy | 716 | |
| 1958 | Asheville, NC, US | H.C. Wilson | 702 | |
| 1959 | Detroit, MI, US | W.I. Meyers | 812 | |
| 1960 | Boston, MA, US | K.F. Amalia | 705 | |
| 1961 | Minneapolis, MN, US | G.J. Lucking | 614 | |
| 1962 | San Francisco, CA, US | K.L. Davey | 519 | |
| 1963 | Toronto, ON, Canada | J.A. Kimmel | 703 | |
| 1964 | Houston, TX, US | O.J. Andersen | 472 | |
| 1965 | Washington, DC | Ray Gustin, Jr. | 816 | |
| 1966 | Cleveland, OH, US | John Michalko | 769 | |
| 1967 | Philadelphia, PA, US | H.R. Johns | 806 | |
| 1968 | Chicago, IL, US | N.B. Wysong | 625 | |
| 1969 | Portland, OR, US | R.R. Stevens | 630 | |
| 1970 | Rochester, NY, US | F. R. Micha | 861 | |
| 1971 | Montreal, QC, Canada | Y. Desmarais | 877 | Trees In Our Environment |
| 1972 | Newport Beach., CA, US | W.T. Bell | 784 | Trees - Our Survival Legacy |
| 1973 | Boston, MA, US | D. Warren, Jr. | 903 | Boston Tree Party |
| 1974 | Atlanta, GA, US | CM Alexander | 866 | Fifty Golden Years and Growing |
| 1975 | Detroit, MI, US | Leslie Toth | 714 | Our Growth Shades the World |
| 1976 | St. Louis, MO, US | F.L. Dinsmore | 756 | Trees Form an Archway to the Future |
| 1977 | Philadelphia, PA, US | RC McConnell | 782 | Tree Care Keeps Our Nations Green |
| 1978 | Toronto, ON, Canada | Mel Melnike | 825 | '78 Crusade for the Preservation of Trees |
| 1979 | San Diego, CA, US | Robert Pletcher | 594 | Tree Awareness ... Our Survival |
| 1980 | Hartford, CT, US | H.J. Cran, Jr. | 670 | Conserve Energy ... With Trees |
| 1981 | B.Falls, MI, US | T.J. Haskell | 736 | A Tree ‘ISA’ Thing of Beauty |
| 1982 | Louisville, KY, US | Larry Lose | 820 | Trees For Today and Tomorrow |
| 1983 | Indianapolis, IN, US | N.P. Engledow | 723 | Trees + Environment = LIFE |
| 1984 | Quebec, QC, Canada | Marc Laurin | 865 | Arboriculture 2000 |
| 1985 | Milwaukee, WI, US | R.W. Skiera | 1036 | Trees and People Need Each Other |
| 1986 | San Antonio, TX, US | Walterscheidt | 755 | Arboles para el Mundo |
| 1987 | Keystone, CO, US | Ronald Morrow | 1089 | Adventures in Arboriculture |
| 1988 | Vancouver, BC, Canada | James Clark | 986 | Arbor Pacifica |
| 1989 | St. Charles, IL, US | Larry Hall | 1201 | Tree Cheers for Arboriculture |
| 1990 | Toronto, ON, Canada | N. Rothenberg | 1172 | ArborOdyssey |
| 1991 | Philadelphia, PA, US | R. McConnell | 1524 | Branching Out to Shape the Future |
| 1992 | Oakland, CA, US | Ken Meyer | 1428 | Discover Arboriculture |
| 1993 | Bismarck, ND, US | Paul Blumhardt | 1123 | Blazing New Trails in Arboriculture |
| 1994 | Halifax, NS, Canada | Steve King | 1198 | Arbor Navigation - 70 Years on Course |
| 1995 | Hilton Head, SC, US | Gary Mullane | 1443 | Southern Hospitality On an Island of Trees |
| 1996 | Cleveland, OH, US | L. Lanphear | 1812 | Arboriculture Rocks the Forest City |
| 1997 | Salt Lake City, UT, US | Alex Morris | 1463 | Frontiers in Arboriculture |
| 1998 | Birmingham, England | D. O’Callaghan | 1252 | Discover Old World Arboriculture |
| 1999 | Stamford, CT, US | Bartlett/Hayner | 1753 | 75th Anniversary - Celebrating Our Roots |
| 2000 | Baltimore, MD, US | Don Blair | 2443 | B2K Is Okay |
| 2001 | Milwaukee, WI, US | Ken Ottman | 2605 | A Festival of Trees |
| 2002 | Seattle, WA, US | Julian Dunster | 2463 | Old Growth and New Technology |
| 2003 | Montreal, QC, Canada | Bruno Paquet | 1882 | Tree Stories – Histoires d’ arbres |
| 2004 | Pittsburgh, PA, US | John Smith | 2100 | Bridging Technologies for Trees of Tomorrow |
| 2005 | Nashville, TN, US | Steve Ketner | 2317 | Trees in Tune |
| 2006 | Minneapolis, MN, US | Don Mueller/Ralph Sievert | 2174 | Hooked on Trees – Arboriculture Up North |
| 2007 | Honolulu, HI, US | Kevin Eckert | 1852 | Catch the Wave of Global Arboriculture |
| 2008 | St. Louis, MO, US | Tim Gamma | 2186 | Gateway to the World of Arboriculture |
| 2009 | Providence, RI, US | H. Dennis Ryan | 1556 | Sailing into the Future of Arboriculture |
| 2010 | Chicago, IL, US | Gary Watson | 2217 | Building the Roots of Arboriculture |
| 2011 | Parramatta, Australia | Robert Sutton | 834 | Trees Down Under |
| 2012 | Portland, OR, US | Terrence P. Flanagan | 2142 | Trees: A Global Necessity |
| 2013 | Toronto, ON, Canada | Paul L. Kobold | 1587 | Trees & People: Growing Stronger Through Diversity |
| 2014 | Milwaukee, WI, US | David Graham | 1903 | Great Trees on a Great Lake |
| 2015 | Orlando, FL, US | Don Winsett | 1401 | Where the Trees Meet the Seas |
| 2016 | Fort Worth, TX, US | James Carse | 1745 | Deep in the Heartwood of Texas |
| 2017 | Washington, D.C., US | Alan Jones | 1750 | One World Under One Canopy |