Appendix 3-2 Palikea Snail Enclosure Re-vegetation Year 1 Summary and Year 2 and 3 Re-vegetation Plan

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1 Appendix 3-2 Palikea Snail Enclosure Re-vegetation Year 1 Summary and Year 2 and 3 Re-vegetation Plan The Year 1 plan spanned from June 2012 to June. Due to reporting timeframes, the plan has been adjusted to match the OANRP reporting year and will extend through September. Some significant re-vegetation contributions were however made before this time period. This summary will cover all noteworthy revegetation efforts made in Year 1 and earlier. Please see Year 1 plan for initial approaches under each heading. Summary of Vegetation Restoration Approaches and Site Considerations from Year 1 Given the relatively high levels of non-native canopy at Palikea, restoration in this enclosure requires a balance of subtracting non-native plants by way of weeding, while continually adding snail host plants. The area where Laminella sanguinea has been found in the enclosure has grown in Year 1. While most snails were initially found in the northwest corner of the enclosure, some were later found in vegetation at the far southwest corner. Snails have been moved from just outside the enclosure to both of these areas inside. Connecting the patches of native vegetation along the western side of the enclosure is a high priority for restoration. Non-essential traffic should remain limited in this area and kept to delineated trails. No Eulandina rosea have been found in the enclosure since February 21,. Inspections of gear and plants brought into the enclosure remains a high priority to prevent E. rosea introductions. Weeding Summary: Weed control of understory weeds was conducted as needed throughout Year 1. A regular suite of weeds continues to recruit in open areas along the walls of the enclosure, but is easily maintained with quarterly sweeps. A considerable amount of Paspalum conjugatum grass established over the winter and covered a great deal of understory throughout the enclosure. This grass was hand-pulled to a large extent. While labor intensive, the effort served both to remove grasses, and to conduct thorough E. rosea ground surveys under the dense grass patches. Hand removal of the grass will continue in the areas with known L. sanguinea, but handcleared areas will be followed up with careful herbicide sprays to control grass more thoroughly throughout the rest of the enclosure. Minimal follow-up sprays are expected after the initial hand-pulling. Phytolacca octandra, Clidemia hirta and Rubus rosifolius were some of the common understory weeds that were also heavily targeted in Year 1. However, after initial control efforts, these weeds are in much lower abundance, and require minimal quarterly weed control. Blecchnum appendiculatum (fern) grows nearby the L. sanguinea area and weed control of this species must be conducted carefully and thoughtfully as L. sanguina forage through leaf litter in the ground. This weed should however remain a high priority target as it forms a dense mat in the understory and is only established locally inside the enclosure. A zero tolerance for Ehrharta stipoides will remain in the enclosure. Patches of this grass continually recruit inside. 1

2 Non-native canopy removal was minimal in Year 1. A small amount of thinning of one of the Schinus terebinthifolius trees took place. Vegetation and wood that did not contribute significantly to the canopy was removed. This effort should continue in Year 2 and ideally all S. terebinthifolius should be trimmed to maintain the amount of canopy shade provided while minimizing total biomass to the bare minimum. Outplants should be started under these trees in preparation for their ultimate removal. Similarly, monotypic P. cattleianum stands should be cleared in small sections and replaced with common native plantings until P. cattleianum is removed. Re-vegetation Summary: Natural recruitment accounted for a small amount of re-vegetation within the enclosure. The patch of Microlepia strigosa at the bottom northeast corner increased in size dramatically with the removal of overstory canopy and continual weed control of other non-native understory competitors. The majority of new plants came from outplants, seed sows and some transplants. Priority areas where re-vegetation was implemented included open areas with bare dirt and low levels of canopy cover, and throughout the A. mustelina and L. sanguinea area. No re-vegetation took place in the buffer around the outside of the exclosure in Year 1. Founder stock for all outplants was collected from rat baiting trails throughout Palikea Management Unit and along the access trail to the unit. All collections are documented with information including how many propagules and from how many founders collections were made. 1) Outplants of greenhouse produced plants summary: The largest numbers of plants planted in the snail enclosure were grown in the greenhouse. A total of 183 plants were planted (Table 1). Year 1 planting goals were not completely met. Very few plants grown from seed were ready to be planted in Year 1, but will be ready instead for Year 2. Timing of fruiting periods and length of propagation time were not well understood for many species and account for delays in outplanting, and lower numbers of plants. This first year served as a helpful learning process to better understand how long it takes cuttings or seeds of certain species to grow to outplanting size. Optimal growing age and pot size will continue to be worked out in Year 2. Outplants were treated with the same sanitation guidelines as followed for rare plant outplantings. All plants were tagged and monitored twice within the first six months of planting. Some species were then monitored every other quarter. Outplantings were conducted in November 2012, March and September. Half of the 35 P. albidis planted in November had Soil Moist polymer granular soil amendment mixed in the media at outplanting. Several plants from this outplanting were not re-located at the first follow-up monitoring interval; however of the plants remaining, the presence of Soil Moist had little effect on vigor at 2 months after planting. The majority of all plants re-located were healthy. The appeal of the product is its potential to supply plants with needed water in interim periods between staff watering within the first couple months of planting. More rigorous field tests with this product outside of the snail enclosure plantings should take place to better understand its utility for common native outplantings in general. 2

3 Overall survivorship for outplants was 75%. This number was higher for most species except the first round of P. sandwicensis. These plants were planted young (only 11 weeks after initial cuttings were taken) to see how early plants could be planted, but did not fare well. All species of plants were most recently monitored in August. Table 1. Outplanting Summary: Species Year 1 #of plants # of plants Planting Comments planned planted alive Date Acacia koa Plant Fruit not collected. Not going forward with original plan; trees too big to put in buffer outside of fence. Will use other species instead. Antidesma platyphyllum Plant September Many cuttings collected, took longer in greenhouse to root and establish than anticipated. Coprosma longifolia Plant September Some difficulties in growth chambers at early stage. Goals will made up in Year 2. Cheirodendron trigynum Plant No cuttings rooted to date. Try more cuttings Year 2 and collect fruit in Year 2 for Year 3 (fruiting in February). Plant Collected fruit this year. Currently germinating in growth chambers for Year 3. Freycenetia arborea Kadua affinis Plant November 2012, September Metrosideros polymorpha Myrsine lessertiana Perrottetia sandwicensis Seed collected and plants growing in greenhouse. Goals made up in Year 2. Plant September Slow growing. Goals made up in Year 2. Plant No fruiting plants found in Year 1. More thorough searches planned for Year 2. Plant November First set of outplants fared poorly. Planted 2012, young and at the end of spring. Many died. March Subsequent outplantings with plants a little older had better success; now well established. Pipturis albidis Plant November 2012, March Urera glabra Plant November 2012, March and September Outplanting finished. Planted in open areas with expectation that will fill in quickly and that these outplants will foster natural recruitment of other taxa. This plant has a quick turn-around for propagation by cuttings. Plants establishing well. Some plants ready for early Year 2 planting. 3

4 2) Seed Sowing Summary: Bidens torta: As seen within the Hapapa snail enclosure, results of the B. torta seed sows were impressive. Seeds were mostly sown on bare ground areas along the inside wall of the enclosure. The plants formed a dense shrub about a meter tall. They will provide shade for outplants slated for Year 2. Seed sows should continue with this species especially as competition for the rapidly growing grass, P. conjugatum. No follow-up watering was conducted for this or any other species. Carex wahuensis: This species recruited favorably from sows as well. Seeds of this species were sown along the inside walls as an effort to promote erosion control along the enclosure wall. This species fruits in April and seeds were sown at that time, but didn t begin to recruit until winter, when water was finally present. All seed sows were conducted with fresh seeds. No seeds were stored, then sowed. However, this strategy may be useful in the future. For seeds that can store at least a minimal amount of time, waiting for wetter conditions may result in even greater results. Coprosma longifolia and Dianella sandwicensis: Seed sows with fruit from both of these species were conducted informally. Fruits were lightly buried in either rows or clumps of fruits respectively. C. longifolia fruits were slightly immature and only blushing red/orange; D. sandwicensis were fully mature. Only C. longifolia seedlings were observed at one plot where additional left-over fruits from the plots were handbroadcast on open soil under overstory canopy cover. On-site germination was also seen with this species in the Hapapa snail enclosure. While outplanting greenhouse plants is likely the best way to establish larger plants more quickly inside the enclosure, further trials should be conducted with both fresh and cleaned seed of C. longifolia in Year 2 to see if seedsows can be an additional restoration method with minimal effort for this species. Pisonia umbellifera: Fruits of this species were sowed in clumps of five fruits each inside the enclosure and 32% of individual clumps have at least 1 seedling present after 1 year. If excess fruit is available, seed sows may be worthwhile, however planting greenhouse grown plants may be the most effective tool for establishing P.umbellifera inside the enclosure. Monitoring: A basic seed-sowing log of what species, how much seed, techniques used, where was sown, etc. will be kept ongoing as long as seed sows take place within the enclosure. Some of the more novel techniques and seeds used may be tracked and trialed more closely while sows of B. torta and C. wahuensis where sowing methodology is known will be marked with pin-flags to prevent trampling. 3) Transplanting/Divisions Summary: Transplants: Some transplanting took place with a variety of species shortly after the completion of the fence; however these plants were not rigorously monitored. Nearly 60 Cibotium tree ferns were transplanted in the enclosure in Year 1. Cibotium ferns were collected from outside of the fence where they were vulnerable to pig obliteration. Ferns were dug out of the ground and rigorously inspected for E. rosea and other pests. The ferns were mostly planted in the open areas at the bottom of the enclosure in large canopy gaps. Nearly every fern established and most have a full canopy of fronds. 4

5 Transplanting is not a favored technique for establishing large numbers of plants in the enclosure. A transplant failure is more costly than a greenhouse propagule. Transplanting is most useful to use for species that are difficult to collect fruit from, difficult or slow to grow in the greenhouse, or that establish by divisions easily. This technique can also be used for more uncommon species where only a few individuals are needed to complete the suite of diversity within the enclosure. Inspection of all transplanted material is critical to prevent E. rosea or other invasive species from being introduced to the enclosure. Transplanting is not a high priority this year as getting large numbers of plants in the ground is still the focus. After Year 3, more emphasis may be placed on transplanting the difficult to propagate, slow growing, rare, etc. types of species. At that time, there may also be more favorable conditions within the enclosure. Divisions: Dianella sandwicensis divisions were collected throughout the MU and planted in and around the L. sanguinea area. Excess dead material, and tops of the plants were cut off; individual divisions were planted and watered at planting. No rigorous monitoring of these took place as earlier successes were noted at Palikea and at the Hapapa snail enclosure as well. Most of these divisions established well, and more work with this species is planned. Restoration Objectives: Palikea Re-vegetation Plan Use re-vegetation and weed control techniques to establish the basis for a native dominated matrix of connected plant communities evenly distributed throughout the enclosure to support a stable population of A. mustellina. Establish % native canopy across the entire enclosure by Year 10. Specific requirements for stable snail habitat are not well documented. Canopy goals are based on assumptions that quality habitat outside the enclosure and historical knowledge of the area should be mimicked inside the enclosure. Outplantings inside the enclosure will discontinue at Year 3. Vegetation monitoring will be conducted at Year 5 to assess the need for additional outplantings in order to reach canopy cover goals. Monitoring protocols will be developed before Year 5 to address vegetation monitoring objectives and identify triggers for management response. Vegetation monitoring objective at Year 5: Assess native canopy and understory levels inside the enclosure. Assess distribution and density of keystone snail tree species in the canopy and understory inside the enclosure. 5

6 Management response: It is unlikely that most outplants will reach canopy height by year 5, and therefore canopy goals are not expected to be met at this monitoring interval. However, snail host tree distribution and % cover of these trees throughout the enclosure may be used as indicators to determine if more outplants are needed. Year 2 Weed Control Action Plan Weed Control Objectives: Conduct gradual canopy weed control to achieve a low level of non-native canopy inside enclosure by year 10. % non-native cover goals to be developed this year with new monitoring specialist. Conduct weed control throughout entire enclosure quarterly, targeting recruiting tree species, weeds identified for zero tolerance within the enclosure, and other priority species. The canopy weed level is currently unknown, but snails benefit from the cover that the non-native canopy provides. Achatinella mustellina are regularly found in P. cattlianum during night surveys for snails. Gradual canopy weed control will continue, and levels will be assessed at year 5. At that time factors such as distribution and cover of native canopy, and stability of snail populations will be taken into consideration when deciding whether or not to continue canopy removal. Quarterly weed control will be conducted throughout the enclosure to maintain low levels of understory weeds. However, control efforts should decrease each year due to weed removal and native vegetation establishment and growth. Weed Control Actions: Understory weed control: o Continue quarterly control of understory weeds inside enclosure as needed throughout the year. o Continue to target zero tolerance weeds including: N. multiflora, and E. stipoides. o Continue high levels of control for B. appendiculatum, P. conjugatum, P. octandra, and R. rosifolius. Overstory weed control: o Thin dead wood and branches from S. terebinthifolius trees. o Slowly begin to remove inside edges of thick P. cattelianum stands (no greater than 1 m strips at a time) and replace with outplants. Conduct regular weed control throughout WCA Palikea-01 (area surrounding the enclosure) as scheduled by the Ecosystem Restoration Program Manager. Re-vegetation Action Plan Outplantings will continue to focus on improving zones of current snail habitat. As these areas become saturated with plants, outplantings will be focused around non-native zones to establish canopy trees that can one day replace non-native canopy. This first year of re-vegetation work in the enclosure has clarified what works, and what is needed. Outplanting goals are set each year based from a combination of the following: 6

7 collection and propagation timing, successes to date, and available greenhouse space. This second year at least 2 planting events are anticipated to achieve outplant goals for Year 2. Some seed collections are scheduled for Year 2, but depending on germination and growth rates, these may not be planted until Year 3. Table 2. Year 2 Outplanting Action Summary Species Current # of plants in field Total # of outplants for Year 2 Collect seed? Antidesma platyphyllum Coprosma longifolia Cheirodendron trigynum Collect cuttings? Notes No No Plants in greenhouse. Plant in early and late winter Seed in storage No Plants in growth chambers and greenhouse. Plant in early and late winter 0 0 Collect for Year 3 Yes No success to date with cuttings from this species; begin to collect fruit and trial growing from seed. Freycenetia arborea 0 25 Seed in storage No Plants in growth chambers. Will not be ready until Year 3. Kadus affinis Seed in storage No Plants in greenhouse. Plant in early and late winter. Metrosideros polymorpha Yes Myrsine lessertiana Perrottetia sandwicensis 6 15 Yes. Collect for seed sow trials, and propagation. Urera glabra No Collect enough to reach goal Pisonia umbellifera Plants in greenhouse. Plant in late winter. Some success with cuttings, but trials to begin this year growing trees from seed. 0 0 Collect for Year 3 No Goal to have 50 plants for year No Collect Plants in greenhouse. Plant in late enough to winter. reach goal Some plants in greenhouse. Collect more; plant in late winter Need to collect for Year 2 or 3 No This species was added to the list after snails found on P. umbellifera outside the fence were indroduced to the enclosure. 7

8 Seed Sow Actions: Conduct seed sows with fresh seed of B. torta, and C. wahuensis as needed in open areas and along enclosure walls to prevent erosion where sloping away from wall. Maintain an open buffer directly adjacent to wall so inspections can be conducted. Conduct more rigorous trials with C. longifolia and any other useful species shown to have some potential seed sow utility. Trial seed sows from processed seed in storage in winter months: K. affinis, C. longifolia. Collect C. wahuensis and store until can sow during winter months of Year 3. Trial M. polymorpha seed sow on hapuu logs. Transplant Actions Collect and plant D. sandwicensis divisions fall/winter throughout enclosure Monitoring actions: Monitor out-plants and seed sow trials Take photopoints quarterly. Year 3 Weed Control Action Plan Weed Control Actions: Continue zero tolerance for the following weed: Ehrharta stipoides Conduct weed control every other quarter targeting but not limited to understory weeds including: B. appendiculatum, P. octandra, R. rosifolius, C. hirta, P. cattleianum, P. conjugatum Continue to thin S. terebinthifolius and P. cattleianum slowly and replace with common native plants. Re-vegetation Action Plan Outplantings for Drosophila stabilization will also take place in coming years at several sites throughout Palikea, one of which is nearby the enclosure. Some plant species will be shared between these two projects but there may be opportunity to plant some of the more diverse species grown for the Drosophila stabilization project inside the enclosure as well. The snail enclosure, actively managed for a suite of pests may also provide benefit to Drosophila species. Table 3. Year 3 Outplanting Action Plan Species Total # of outplants for Year 3 Collect seed? A. platyphyllum Collect cuttings? 8 Notes - No If needed Assess state of enclosure after last winter outplanting. Collect cuttings if more plants needed.

9 C. longifolia - Seed in storage No Assess state of enclosure after last winter outplanting. Sow seeds early spring if needed. C. trigynum 35 Collect in Year 2 Yes; continue to trial Army staff to work out best propagation practices for this species. Simultaneously trial seed and cuttings. Plant all available plants. F. arborea 25 Seed in storage Collect more seed K. affinis - Seed in storage If needed Assess state of enclosure after last winter outplanting. Sow seeds early spring if needed. M. 25 Seed in storage No Plants will be grown from seed in polymorpha Year 2. M. 50 Collect in Year No Need to locate seed sources in MU lessertiana 2 in Year 2 and collect. Perrottetia - No If needed Assess state of enclosure after last sandwicensis winter outplanting. Collect cuttings if more plants needed. U. glabra - No If needed Assess state of enclosure after last winter outplanting. Collect cuttings if more plants needed. No P. umbellifera 25 Collect in Year 2 Collect and sow as available. Fruits do not store. 9