Oceanspray Management CPOP Listserv Discussion Suggestions for managing Oceanspray Summary In October 2014, Chris Junck (Garry Oak Ecosystems Recovery Team Society) emailed the listserv on behalf of a B.C. landowner with dense Oceanspray (Holodiscus discolor) around Garry Oaks. He asked if anybody had suggestions for controlling the Oceanspray in order to plant other native species. Elaine Stewart (Portland Metro-Natural Areas Program) replied that she had not contemplated controlling Oceanspray as it is a nice native plant and generally doesn’t cause problems. Nonetheless, she mentioned that it could be pruned back to help oaks establish. Thomas Brian Maertens (Bigleaf Biogeography Unlimited) agreed with Elaine Stewart and added that there is not much Oceanspray in yards in B.C. and recommends that neighbors simply maintain it. Several others agreed that Oceanspray is desirable, supporting bird diversity and hemiparasitic plants. Chris Junck clarified that the stand is very dense and crowding out other natives, so the landowner would like to knock it back to improve diversity. David Perasso noted a similar situation with snowberry and recommended mechanical removal or coppicing. Keith Perchemlides (TNC) also had similar experience with buckbrush in Southwestern Oregon, generally due to lack of fire, and recommended radial or mosaic thinning followed by planting of other natives to reduce the threat of ladder fuels. Richard Hebda recommended management by pruning out dead and previously flowering branches as well as plants overshadowing oak seedlings. Dave Hays (WDFW) recommended cutting and spraying the stump with garlon, or cutting and allowing deer to browse. Reba Olsen recommended removal using a weed wrench. Jon Kemp added that the Oceanspray should tend to become thinner as the oaks mature. Suggestions for Managing Oceanspray 1 Oceanspray Management Original CPOP Listserv Messages The CPOP Listserv Archive can be found for subscribers at listserv.wa.gov. To subscribe to the CPOP Listserv visit our website at cascadiaprairieoak.org. October 16, 2014 – Chris Junck (GOERT) Hi, A landowner in BC is seeking best practices info for managing a dense growth of Oceanspray (Holodiscus discolor) around his Garry Oaks. He wants to plant other native species after he gets the Oceanspray under control. Does anyone have suggestions that I can pass along? Cheers, Chris Junck Habitat Conservation Facilitator Garry Oak Ecosystems Recovery Team Society Please note our new address: 1500E Admirals Road Victoria BC V9A 2R1 Office: (250) 383-3445 www.goert.ca "A lifeline for our rarest species" October 17, 2014 – Elaine Stewart (Portland Metro-Natural Areas Program) I have to confess that I have not contemplated controlling Holodiscus. Does the landowner think it’s competing with the oaks? I have not seen it become a problem in my area, and I have a hard time imagining it becoming a problem. If your landowner is worried about it shading out small oaks, maybe he could just prune it a bit. It’s such a nice native plant. -Elaine Stewart Suggestions for Managing Oceanspray 2 Senior Natural Resources Scientist Metro - Natural Areas Program 600 NE Grand Ave Portland OR 97232-2736 503.797.1515 503.797.1849 fax October 17, 2014 – Thomas Brian Maertens (Bigleaf Biogeography Unlimited) Like Elaine, I also consider oceanspray a desirable native. I have noticed a distinct lack of oceanspray in people's yards in BC (not full and bushy like many ornamentals) and have recommended to my neighbours that they maintain what oceanspray they have. Again like Elaine, I can see pruning oceanspray around young oaks to get them established. I can think of 100 other plants more detrimental to oaks and prairies than oceanspray! I am curious about others' opinions here and will follow this thread. Cheers Thomas Brian Maertens Bigleaf Biogeography Unlimited October 17, 2014 – Chris Junck Apparently it is growing very densely and is crowding out the other native vegetation. I think he just wants to knock it back and manage it so that he can have greater diversity around the Garry Oaks (rather than a monoculture), and perhaps better recruitment of oak seedlings. Chris October 17, 2014 – David Perasso I have faced similar problems with snowberry (Symphorocarpus alba) which dominates under the oaks at the park I work at. We remove it (gradually) and plant other species. We will always keep some, but we want to take it from 100% of the native cover to 25%. So I totally support the idea (assuming he’s got a good plan in place). Suggestions for Managing Oceanspray 3 As for removing it, like others on this list, I have never set out to deliberately “weed out” a stand of Holodiscus. That said, I have had to remove the occasional plant and they don’t come back. I would think that mechanical removal (shovel, mattock) would be the best way to remove it and if you get most of the root, there shouldn’t be an issue with it coming back. One interesting possibility would be to coppice some it. Native Peoples used to coppice Holodiscus to cause it to grow straight stems for various uses. Holodiscus is an “ironwood”. Coppicing would also allow other plants to grow around the base of the Holodiscus as they would no longer be shaded out. good luck, David Fight Nature Deficit Disorder Let no child be left inside October 17, 2014 – Jon Kemp (EnCo Environmental Corporation) Hi: Based on my experience in the field Oceanspray thrives best at the outer edge of forests/tree stands. It likes a lot of sun and it likes drier soils. It will grow in the shade but the width of the plant will me much narrower than the wider stands at the outer edge. When the sapling trees get taller the Oceanspray will become a narrower plant. I agree thinning the plant stand should help. Jonathan Kemp, Principal EnCo Environmental Corporation P.O. Box 1212 Puyallup, WA 98371 Work: 253-841-9710 Email: [email protected] October 17, 2014 – Keith Perchemlides (The Nature Conservancy) Suggestions for Managing Oceanspray 4 We find ourselves in a similar situation with dense single-species stands of buckbrush (Ceanothus cuneatus) around Garry oak in SW Oregon – typically due to extended lack of fire disturbance. I agree that these native shrubs are a welcome component of the system – but also that they can dominant to the exclusion of other natives. As I read it, your interest is more in understory restoration – promoting native diversity – rather than protection of oaks. We have recommended radial thinning (around oaks) or mosaic thinning of Ceanothus followed by sowing or planting of other native species. Where Ceanothus is dense around oaks it certainly can present a threat as ladder fuel – in this case, radial thinning around oaks is also a reasonable pre-treatment before prescribed burning or to increase oak survival in wildfire. I’m not sure about oceanspray, but buckbrush actually seems to facilitate oak recruitment by providing microsites for seedling establishment. Keith October 17, 2014 – Richard Hebda I have quite a bit of experience with Oceanspray. It does not need control but it can be managed by pruning out the dead branches and branches that have flowered the previous year to a vigorous up –side shoot. This reduces the wide spread of low dead and dying branches and markedly opens the understory. The land owner could consider removing weak individuals that are being over-shadowed too. The effect of this management is a very attractive open understory covered in moss and will support attractive growth of Erythronium oregonum. If oak is to be encouraged then reduce ocean spray canopy above seedlings by pruning to let the oaks establish vertical growth and grow through Ocean spray cover. October 17, 2014 – Dave Hays (Washington Department of Fish and Wildlife) Cutting holodiscus and spraying the cut stump with garlon works. Also, if they have a lot of deer, holodiscus is a favorite deer browse, and can be kept in check for a number of years through simple cutting at the base of the plant. Sometimes that works well and sometimes it does not. Dave Hays Washington Department of Fish and Wildlife Wildlife Program Suggestions for Managing Oceanspray 5 October 17, 2014 – Reba Olsen For removal, I would think that a Weed Wrench would work nicely. Weed Wrench is a woody plant puller that is very effective. It comes in 4 sizes. Google it. October 17, 2014 – Susan Morre (Botanica Landscapes) I also consider oceanspray a desirable native and have seen it growing a bit more robustly at the edge of an oak woodland, but less so where there is more canopy cover. I have not encountered a situation where it appeared to be inhibiting the vigor of nearby oaks. Susan Morre Botanica Landscapes Corvallis, Oregon October 17, 2014 – Edward Alverson For what it is worth - Dave Vesely of the Oregon Wildlife Institute mentioned to me recently that ocean spray has been observed to support a particularly high diversity of songbirds relative to other native understory shrubs. I'm not sure why that might be the case, but perhaps there are many insects (bird food) that live on ocean spray. It would be a worthwhile topic to explore in greater detail. This kind of makes sense if you consider that Holodiscus is a genus primarily of western North America (a few species extent into Latin America as well), and likely has a very long and continuous evolutionary history here (and thus opportunities for coevolution with insects). Fossils assigned to Holodiscus are known from the Florrisant flora of Colorado, which dates to the Eocene, about 34 million years ago. Ed October 17, 2014 – Lori Hennings (Oregon Metro) Ocean spray is a major caterpillar host.