By Nancy J. Bissett The Natives

Transcription

1 Restoration of Native Ecosystem Groundcover by Direct Seeding Methods and Examples By Nancy J. Bissett The Natives 1

2 Reedy Creek Mitigation Bank Over 186 acres of bahia pasture were converted to scrub, scrubby, mesic, and hydric flatwoods, and seepage slope by intensive site preparation, seeding, and planting. Bahia Pasture Before Restoration Bahia Pasture Before 2

3 Site was herbicided until all exotics were dead. Then it was disked and rolled to chop rhizomes and achieve flat seed bed ready surface. Harvesting seed with green silage cutter 3

4 Hand collecting seed at special times and for special places Hand-collected seed are sorted into lots for each target ecosystem PROJECTED ECOSYSTEM DEVELOPMENT FOR THE REEDY CREEK MITIGATION BANK PHASE II UPLAND RESTORATION SITE 4

5 Seeding bulk seed and stems Essential parts of good seeding Cultipacker Adding site specific seeds Rolling 5

6 Irrigating dry areas produces many seedlings, but it is not necessary with adequate rainfall. Dry mesic flatwoods 3 years after seeding 6

7 Scrub to scrubby flatwoods, 1 ½ years after seeding Lopsided indiangrass in bloom in mesic flatwoods 7

8 Wicking tall dogfennel with glyphosate. leaves the desirable vegetation underneath unharmed 8

9 Plateau herbicide sprayed over wiregrass and blazing star Dead and dying bahia spreading from native cluster Photo at right with bahia grass covering much of the site At left is the same site one year after the application of Plateau herbicide. 9

10 Corkscrew Threeawn and other species reseeded in wet winters. October flower Blazing star Splitbeard bluestem Wiregrass Yellow buttons Lopsided indiangrass In dry mesic flatwoods 10

11 Hog damage was revegetated by blue maidencane grass Hartwrightia is one of twelve rare plants seeded, planted, or preserved din the restoration area. From handcollected seed there is now a blooming population on the seepage slope. 11

12 Hooded Pitcher Plant (Sarracenia minor) was seeded onto the site and Fallflowering Ixia (Nemastylis floridana) was preserved. Prescribed burn in May

13 Fire reduced unwanted shrubs and increased The burn wildflower reduced bloom. shrub cover and increased wildflowers. Redtop Panicums (Panicum longifolium and Panicum rigidulum) 13

14 Wildflowers on the seepage slope included blazing star, goldenrod, and rayless sunflower. Star clusters, Barbara s buttons, and dtoothache th h grass were also seen flowering. Wiregrass produced lots of seed. 14

15 Purple lovegrass, Elliott s lovegrass, bluestems, and silver-leaved aster offer color and texture. Monitoring quadrats 15

16 % Cover for Indigenous Species, Indigenous Grasses, and Exotic Species for Mesic Flatwoods: % Cover Monitoring Year Indigenous Species Indigenous Grasses Exotic Species The cover of indigenous species ranges from 75% for scrubby flatwoods, to 83% in mesic, and 92% in hydric flatwoods after 5 years. 16

17 PERCENT COVER OF WIREGRASS: PERCENT COVER SCRUB-SCRUBBY FLATWOODS MESIC FLATWOODS MONITORING YEAR Shrubs were planted the summer after seeding to provide all layers of the restored ecosystems. 17

18 The diversity of species in the seeded areas that are native to these systems is 277 species. 18

19 Persistent Exotics Bahia Grass ( Paspalum notatum) Cogon Grass (Imperata cylindrica) Natal Grass ( Rhynchelytrum repens) Torpedo Grass (Panicum repens) Bermuda Grass (Cynodon dactylon ) Bahia Grass ( Paspalum notatum) 19

20 Natal Grass ( Rhynchelytrum repens) Seed can germinate in 1 day. Natal grass readily seeds into disturbed sites and can produce new seed within 6 weeks. Does natal grass have a short seedbank life? Precision application: Herbicide was applied to center of natal grass on each side of cutthroat grass Sites were maintained by spot spraying several times a year. Pre-emergent is used to control germination. 20

21 Cogon Grass (Imperata cylindrica) Torpedo Grass (Panicum repens) 21

22 Toropedo Grass Dominated Cypress Pond Before... January 2006 After. July 2006 After.. January 2009 After.. January /3 of this site was covered with heavy torpedo grass After one year and 2 herbicide applications much live grass persisted From a 6 inch whole layers of live and dead rhizomes 22

23 Chisel Plow and Field Cultivator Chisel Plow raked rhizomes to surface. Another herbicide, then plowing and cultivating, then spot spraying remaining sprigs that were about 10 apart. Bermuda Grass (Cynodon dactylon ) 23

24 Site Preparations Problems - Not Dead Enough Uneven site preparation inhibits good seed-soil contact 24

25 Plants and poles left on the site allow for pockets of invasive species and uneven seeding. 25

26 Dry Prairie ie Groundcover o Seeding A cleared area was seeded from a nearby machine harvest to restore 9 acres in Pasco County in months after seeding 26

27 A Wet Prairie A Wet Prairie Portion Grading to Dry Prairie 27

28 Lake Nona South Mitigation i i Within a Development Forty four acres were stripped, topsoiled and seeded. d 28

29 Herbiciding and disking 5 years previous caused deep rooted bermuda and torpedo grass. Site was stripped of the top 6 inches of soil. Donor site was burned in early July to produce wiregrass seed and less topsoil material. T il f d Topsoil from donor flatwoods was spread 6 inches deep. 29

30 Where excavation was too shallow torpedo grass persisted. Seed was harvested from donor site and seeded in mid-november. 30

31 Plants from roots in topsoil and seed are emerging on the site for restoration of groundcover and shrubs. 11 months after seeding 31

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33 Lake Wales Forest Mitigation Site A 400 acres site was covered initially with a bahia grass pasture. Ecosystem targets included scrub, sandhill, scrubby flatwoods, mesic flatwoods, hydric flatwoods, seepage slopes, wet prairies, marshes, cypress and bay swamps. The tall vegetation was mowed and hayed before herbiciding idi to get an even coverage by the glyphosate herbicide. 33

34 All of the pasture grasses were killed before disking, seedling weeds are disked. Some sites may get too wet in the summer to properly prepare. Allow for a sufficient site preparation window. Culters tucked palmetto fronds into ground,... helping to prevent wind and water erosion. 34

35 An existing wet prairie was dominated by carpet grass, Axonopus furcatus. We mowed it short and applied a single application of glyphosate. This reduced the cover of carpet grass and dramatically increased the number and cover of wet prairie species. Seed of many upland species were hand collected and added to seed mix. 35

36 Lovegrasses all perform well for roadway seeding. Acorns and hickory nuts were hand planted as they ripened Saw palmetto and scrub palmetto seed were added to seed mix 36

37 A diverse upland seeded area in the foreground. 37

38 On a Green Swamp Sandhill Site 200 Acres Were Seeded on Former Bahia Pasture A hydroaxe was used to prepare donor site Donor site after hydroax treatment 38

39 Bahia grass germinates readily on drier sites from the seedbank. Two methods were used to control it. Site was fully prepared by August. Bahia seed that germinated was herbicided before seeding. Imazapic (Plateau) was also applied in June, 6 months after seeding. Bahia grass seedlings were controlled and the native species flourished. 39

40 Site has been burned at least twice. Alternative Harvesting and Seeding Methods 40

41 Flail Vac Seed Collector Seeding with a Grasslander 41

42 The Grasslander can sow trashy seed The seeder must be calibrated for adequate seed dispersal. 42

43 Native grasses and forbs were seeded on washed sand tailings and irrigated with water guns. Added scrub species include sandhill wireweed, October flower, Chapman s goldenrod, and more Wiregrass and lopsided indiangrass were reduced in size on scrub soil. 43

44 Many hand-collected scrub species thrived. Timing of Seeding Events and Climate from USGS Circular 1137 (1998) 44

45 Many factors that made this difficult Old Naval Air Station debris and exotics Construction dumping Very heavy weed seed bank Trail and earthwork not completed Bermuda grass and it is August with no contract to start work 45

46 Reseeding and seeding all of site, January 2008 Edges and slopes are hydroseeded to prevent erosion. 46

47 Balm Scrubby Flatwoods 22 months after seeding 47

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