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workable option in a garden such as Owen, with over 400 it ° , .. i±kfl ► . ' " j
<br /> varieties on display. Thompson and Heard's work has proven that _ ' s. .t.1; '; ,�. '' •
<br /> it is possible to have it both ways —a beautiful, classic display • 'a • -'" ., wh , .
<br /> garden on the one hand and little or no use of synthetic fungicides „ a w :
<br /> on the other. ti:~
<br /> Here, again, the foundation of the program is healthy plants, "� ` •' A• _ '
<br /> g P g YP a a ,
<br /> assisted by the natural micro of the site and intelligent , -' „fie..,► - -^ •
<br /> human management. "It all starts with a thorough pruning in a ti „;y .- .c" " �, ` ,'
<br /> January," explains Heard. Weak, small growth that will not "' � n ,,'`�'s`r"'�` r; �; Sy� '
<br /> support a bloom is removed. Such growth is often where disease';` -1'r' ,,,Y..'s•s- „''' ;'
<br /> su y ..:.
<br /> PP g ,�� � x Ra^ S� ;. , ' • <;;l,, +*tom:•
<br /> be Both men agree that healthy growth is rarely infested 4 ., ' ,x . . +y . � i r ye , 11%'1.;.---,r---/:
<br /> �<
<br /> initially, unless it is near the weaker stems. Pruning techniques ; .41v,: e ,... s - - -.414. * '^ ' 4 '' ` , Z?
<br /> are assisted by good airflow throughout the site from a steady ?. 4. r``• ' *1 ' • ro ...;
<br /> breeze off the adjacent Willamette River, a monthly fertilizer ,,, is h, 4 r ' ` x,,� 7 '- 4,,.i'r u A� ■
<br /> program throughout the growing season, adequate irrigation ' ° .e*' ,. ; N , 4 ; • ti
<br /> (timed for the early morning hours) and the thorough washing r = 4t. ?e 'i' . �. ,r:;°+ > ►+ . ,..,V.",...4.-. '
<br /> provided by the pop -up, shrub spray irrigation heads. � �;�� ,, � •'���, • � ,q
<br /> Thompson also believes his transplanting techniques contrib `' w .'' i �' ►*►. ^.
<br /> ute to the health and disease - resistance of the garden's roses. }� , , s a'';':1%.:-'' r �r: _ `
<br /> ., � ,:,- r , ,,
<br /> "Digging up roses and replanting them stimulates them," he says.
<br /> The Garden staff moves and divides plants regularly. Early fall Colorful mass plantings surround a rustic garden structure.
<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 corn-
<br /> ,
<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 /> • - " • . . ice' + visited gardens with intensive spray programs that had as much
<br /> - +► +'' -!' ��, ; .•• rust as Owen does without one asserts Thompson. He also
<br /> y �.�,:;. , e`�, i '� . 1,. 1.;, _- believes dried spray materials on foliage can be unsightly and that
<br /> ••. -40,'..t.:4-. t f r
<br /> -_• Y •--v �- r v +r 4 y ,••., . 1 too- frequent use of p esticides has negative effects on the health
<br /> • '.,,' � " �'''I r?•��P+swY•' ,, "w+:c ` ,�'�� and vigor of roses. As two examples, he cites damaged buds and
<br /> v ,�►1s ;te -s • i y 5 f 41, • ; "ee .,,•.^,� : shoots resulting from ac of dormant spray materials
<br /> ,4`.•n. vw :. a +'e••:/ 1. s 1. '" at the leaf axil and the lu in of stomata b miticide and
<br /> s S
<br /> ' ».`� '�3-,� ex.‘..., ? `' ,E 4 ,.. y '
<br /> , P gg g Y
<br /> 't+: �.: _. y'
<br /> ' 'e� - +�• = * "� w � ' &: 4'" �" 1 " 4 " ..• ar.4 . fungicide applied to the underside of leaves. We have enough to
<br /> �;* � -•a. ; .� • f , .� � ;: .... , _ do around here without insulting the roses with spray," he says.
<br /> r : - :'> •* ,„„�. " I used to apply more pesticide than all the other applicators
<br /> r ;• `1 • . . • `r . ; � ..ti..7t '? �.. -• ""fi., (in the Parks Division) combined," adds Heard. "Sometimes it's
<br /> 11 • ` '" '"1 '" ` amazing what you can do without." Over 4,000 roses in their
<br /> ..*:. nine -acre, classic style garden testify that five, calendar-
<br /> c.;, E vt ,z i ti 3 i. .+ Y g Y pre-emptive, P
<br /> .. . > = :s..'' y , . ,s driven insecticide /fungicide cover spray programs are expend - •
<br /> 4 � •- "'f aK �,; ` 4 . - • able. And just as eloquently, they proclaim that experienced and
<br /> '- '':" r '' . ' '''''''41:"41.--'''5'''' _, • r'' - 7 ' - ' 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. ,
<br />
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