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workable option in a garden such as Owen, with over 400 '..;. 4 ' ,:.s ;
<br /> varieties on display. Thompson and Heard's work has proven that `: ' • ' , P.. , • k _•
<br /> it is possible to have it both ways —a beautiful, classic display 4".. ,
<br /> garden on the one hand and little or no use of synthetic fungicides ' `vi►` M - ,
<br /> on the other. - .
<br /> . .
<br /> Here, again, the foundation of the program is healthy plants, ; , .,•' .. .
<br /> t:
<br /> assisted by the natural micro - climate of the site and intelligent • rt ' ,z �:..� ^.
<br /> human management. "It all starts with a thorough pruning in t 1.- % - ° � +r',.;; :":,- J - - - �: ' ,.•- .Z• •
<br /> January," explains Heard. Weak, small growth that will not - ° ` ,. • 1 f ' ,
<br /> support a bloom is removed. Such growth is often where disease �. - ,- : -'- .- • ' y'" `..
<br /> ' ,• r
<br /> begins. Both men agree that healthy growth is rarely infested a 71 r F ° " y •
<br /> initially. unless it is near the weaker stems. Pruning techniques �‘ -. - ; : '� - - r ' 9.; .
<br /> -
<br /> , i ",; 4" :' -_ -', - 4a' 1 f *, 40,•-- _;ill;. -• - 2' - -
<br /> are assisted by good airflow throughout the site from a steady -,,,..i., -r . . . r{' S • •;•
<br /> 1 : -, �' R r �_' e-,> � - � ' , .> .a , -- n -
<br /> breeze off the adjacent Willamette River• a monthly fertilizer _ - " � C . ... 1 - •
<br /> program throughout the growing season, adequate irrigation , r ,,d_ � � •7! �
<br /> ' ti'{ • . ._,, -T . ` •
<br /> . .04.1i
<br /> (timed for the early morning hours) and the thorough washing " *• • ' •t ., ,. ^.► . rt .11111.-.1- •l...` ,;, .
<br /> provided by the pop -up, shrub spray irrigation heads. . r .. ;.S . , .6. "• ..., • `'+'. .4 ,
<br /> Thompson also believes his transplanting techniques contrib- 4 "" •. 4" • - ; 1' e AMA.; `; "i -,
<br /> ute to the health and disease- resistance of the garden's roses. '� . -- r " � „ ' r:. s� --
<br /> "Digging up roses and replanting them stimulates them," he says. Colorful mass plantings surround a rustic garden structure.
<br /> The Garden staff moves and divides plants regularly. Early fall
<br /> is considered the optimum time, but transplanting continues would yield the lowest non - target impact without compromising
<br /> throughout the dormant season in a typical year. Roses are necessary standards for disease control. This initial effort was
<br /> planted with the crown about two inches below the surface, successful in reducing necessary "growing season" treatments,
<br /> causing the plant to root out on the crown. This avoids basal but Thompson and Heardwere convinced they could do even
<br /> shoots from the grafted rootstock, and both the Head Gardener better. In 1985 -86, they decided to try to do without any pre-
<br /> and his assistant believe it also contributes to winter- hardiness emptive fungicide applications. They had already voluntarily
<br /> and disease - resistance. ceased insecticide use in favor of predators and water - blasting.
<br /> Some rose varieties particularly prone to rust were moved Their willingness and success are a powerful validation of the
<br /> from the upwind to the downwind side of the garden to inhibit the Division's original decision to train field staff in IPM principles
<br /> spread of this disease. and techniques and encourage them to use their own creativity in
<br /> Another technique worth consideration is the grouping of dis- applying these to the specific weed and pest control problems
<br /> ease -prone varieties together in blocks so that fungicide applica- they faced.
<br /> tion can be limited when/if treatment of these plants becomes In the case of the Owen Municipal Rose Garden. Glenn
<br /> necessary. "There have always been varieties that didn't need Thompson's twenty -four years of site - specific rose care experi-
<br /> spraying— they aren't susceptible," Thompson observes, adding ence and Paul Heard's eleven years as his assistant have com-
<br /> that it is a waste of time to spray such plants. Biodegradable soap/ bined to produce a truly revolutionary system of insect and
<br /> sulfur fungicides for roses are also available on the market and disease control using IPM methodology. Their success has sur-
<br /> can be tried before resorting to more toxic materials. passed all expectations, eliminating the regular use of synthetic
<br /> When Eugene's IPM program began, it was believed that a insecticides and fungicides and earning in 1987. even while this
<br /> strong preventive program, stressing dormant season applica- was being done, a Certificate of Award as an "Outstanding Rose
<br /> tions of milder materials such as lime- sulfur and dormant oil, Garden" from All- America Rose Selections.
<br /> As the program's designers, they are also its promoters. "I've
<br /> .•: i Aga; •+- ' visited gardens with intensive spray programs that had as much
<br /> t. ' .4..,� -_ • rust as Owen does without one asserts Thompson. He also
<br /> . • 1 �, believes dried spray materials on foliage can be unsightly and that
<br /> • • ', 1 • too- frequent use of pesticides has negative effects on the health
<br /> • -, , • •-••••• , ' and vigor of roses. As two examples, he cites damaged buds and
<br /> • 111 n . - .: � .. -. • p. . ':. 7. . }
<br /> �, i .:.. ; ; ` _ shoots resulting from accumulations of dormant spray materials •
<br /> - -4 , n.`C at the leaf axil and the plugging of stomata by miticide and
<br /> .1‘44 � . 4 - • ,r •' - .; y = •." ` fungicide applied to the underside of leaves. "We have enough to
<br /> tn ' � do around here without insulting the roses with spray," he says.
<br /> •. -• ^ "�• s - •'7. f?, •'' "I used to apply more pesticide than all the other applicators
<br /> ' "' (in the Parks Division) combined," adds Heard. "Sometimes it's tor - �.r k , - �� amazing what you can do without." Over 4,000 roses in their
<br /> 1.i_ • ' - ;'• Y � - ` - t" -" nine -acre, classic style garden testify that pre - emptive, calendar-
<br /> - ^ "..>
<br /> • � .. • ' - 4 , -. ,_ ;.
<br /> driven insecticide /fungicide cover spray programs are expend-
<br /> 1, - - - • able. And just as eloquently, they proclaim that experienced and
<br /> dedicated rosarians will continue to develop new and better ways
<br /> Broad walkways provide easy access for visitors among the to care for the plants whose unique beauty is appreciated by so
<br /> banks of rose beds set against the wall of colorful climbers. many.
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