Native Grasses & of Arid and Semi-arid Regions

Technical Note No. 13 | Erosion and Sediment Control Guidelines

Description dormancy rate. When determining sowing rates, it Native grasses and plants are a key component to is tempting to spread seed thinly to make it go a healthy, functional vegetation community and further. However, in the field, only a very small provide protection to the soil while reducing the percentage of seed will successfully germinate potential for weed invasion. On land where and establish. grazing, vehicular traffic and development have a high impact, native vegetation vanishes in the Some seed will require treatment to assist in process. This the soil bare and prone to germination. Further information can be obtained erosion and invasion by weeds. from Greening Northern Territory.

Application and Function The key requirements for sowing are: Native vegetation communities provide food and shelter for native animals and birds as well as •A sowing depth of 5-10mm. protecting the soil from erosion. •A close seed-soil contact. To restore vegetation to a site, the ideal choices •Hand broadcast seed onto ripped, cultivated soil are: and lightly cover seed with a rake or mesh towed behind a vehicle. •The species that grow in the surrounding areas •Agricultural seeders can be used to sow seed, or what grows on similar sites. but check that the sowing depth is in the 5-10mm •Grasses from which you can get seed (i.e. are range. there any existing stands to harvest?). Seed germinates during the warmer months. The Due to the lack of commercial supply, seed must best time to sow is just before rain during warmer be collected from naturally occurring stands. Keep months. Based on historical rainfall data the best in mind: time to sow is:

•That most seed is produced following summer •November in the arid regions. rain. •September in the semi-arid regions. •Ensure you get mature seed; harvest when some seed is just beginning to drop from the . If sown seed can be irrigated by sprinkler, the •Seed drop usually begins about one month after chance of success is greatly improved. seed heads begin to develop. Germination usually occurs within eight days of •Harvesting seed by hand is a simple matter of rain if the following conditions are present: pulling seed heads off the stand. •Collect as clean a sample as possible to avoid •Healthy seed. the need for seed cleaning. •When the soil remains wet for three or more days. Examine a sample of the seeds for seed fill. Pull •Warm soil which is why germination is restricted the outer layers away and see how many have a to the warmer months. small hard grain inside (some may have more than one) usually this is good viable seed. If seed Not all of the seed germinates when the right is to be stored, ensure that: conditions arise, some will lay dormant in the ground until next time. This is the seed’s natural •If the freshly harvested seed is moist then spread defence against false starts, because it ensures it out in an open area for a few days to air dry. that if the first seedlings do not survive then there •It is stored in a cool, dry area. are more seeds ready to germinate when the right •It is stored in a container or bag that allows some conditions arise again. Keep in mind that: air movement. •High seedling death is normal for the first few weeks. The ability of most native grass and plant seed to germinate improves during storage over the first Limitations one to two years. After about four years storage Certain native species have specific soil, nutrient the seed quality begins to decline. and water requirements. Depending on the location of the land, the amount of available water When sowing, it is best to use seed that is at least and/or rainfall, the choice of species may be a year old due to fresh seed having a high limited.

DEPARTMENT OF LAND RESOURCE MANAGEMENT www.lrm.nt.gov.au

Advantages Unfortunately, there is no guarantee of success Vegetation is the cheapest form of protection where re-seeding in arid areas is concerned. against soil erosion. Vegetative cover and surface Maximise opportunity for success by selecting the litter absorb energy from raindrops, thus reducing right grasses and plants, sowing good seed, and the amount of splash (raindrop) erosion. paying attention to details like sowing depth. Vegetation also reduces the direct contact between raindrops and the soil. Having a good When the right rainfall is received germination will cover of vegetation reduces the susceptibility of most likely occur and over time healthy and soil to wind erosion and enhances the infiltration persistent native grasses and plants will establish. of water. Sensible management will allow the established stand to persist and spread. Alternatives Some introduced species of grasses and plants The attached lists have been prepared from a grow surprisingly well in the arid zone and have variety of sources to aid in the selection of species been used successfully in dust suppression and of native grasses and plants suitable for Central erosion control projects. Be careful not to plant Australian conditions. species that are recognised weeds or are likely to become invasive (e.g. Athel Pine, Mossman River Contact details Grass, etc). If you are not certain about a For further information contact the DLRM Land particular species speak to your Regional Weeds Management Unit in your region. Additional Officer. Technical Notes and Erosion and Sediment Control Guidelines are available on the website: Maintenance http://www.lrm.nt.gov.au/soil/management The success of revegetation, using native grasses and plants, is dependent on root development Land Management Unit - Rangelands Division before a dry period. To maintain the vegetation Darwin: Phone (08) 8999 4572 ensure that: Level 3, Goyder Centre, Palmerston •Grazing by feral animals (e.g. rabbits, camels), is Katherine: Phone (08) 8973 8838 controlled. 32 Giles Street, Katherine •Grazing by livestock should be deferred until after Alice Springs: Phone (08) 8951 9208 the first growing season when the plant has Tom Hare Building, Alice Springs produced seed. •The first grazing should be light.

DEPARTMENT OF LAND RESOURCE MANAGEMENT www.lrm.nt.gov.au

PERFORMANCE OF NATIVE GRASSES USED IN RE-SEEDING TRIALS IN CENTRAL AUSTRALIA

SPECIES SEED COLLECTION GERMINATION & PERSISTENCE POTENTIAL FOR USE ESTABLISHMENT IN RE-SEEDING PROGRAMMES

Barley Mitchell Grass     Astrebla pectinata Grows in large open Seed germinates Plants tolerate dry Broad application on stands. Ripe seed readily. Not too conditions and mature heavy soils. retained on plant. Seed sensitive to sowing rapidly. easily removed. depth. Seedlings are hardy. Desert Blue Grass     Bothriochloa Dense stands in open Seed quality is Seedlings are very Broad application on ewartiana areas can be found. Ripe sometimes poor. Good hardy. Mature plants heavy soils. Poor seeds drop rapidly. seed germinates are drought tolerant. palatability may be an readily. inhibiting factor. Native Millet     Panicum Large pure stands Germinates readily. Will form dense Good in a mix with more decompositum uncommon. Seed easily Seedlings grow rapidly, stands, but requires persistent grasses. removed, but cleaning but will not tolerate dry favourable conditions required. conditions. to persist. Native Oatgrass     Enneapogon Grows in large open Seed fill is often poor. Normally behaves as Especially useful on avenaceus stands. Timing of Seedlings will tolerate an annual, but may sandy soils, but poor harvesting is important dry conditions and persist longer under persistence is a problem. because mature seeds mature rapidly. favourable conditions. drop rapidly Queensland     Bluegrass Timing of harvest is Germination is Requires favourable Useful in a mix with more Dichanthium important because sometimes poor. conditions to persist. persistent grasses. sericeum mature seeds drop Seedlings will not rapidly. Does not occur tolerate dry conditions. in large stands. Windmill Grass     Oxychloris pectinata Occasionally occurs in Germinates readily. Short lived annual. Useful on hard-setting dense pure stands. Seed Matures rapidly. Spreads rapidly. scalds where it is easily removed. Seed establishes readily. forms dense clumps Good in a mix with more which makes handling persistent grasses. difficult. Curly Windmill Grass     Enteropogon Seed difficult to remove. Germinates readily. Plants do not persist. Seed availability and high acicularis Does not occur in open Most seedlings die. death rate of seedlings stands. are major constraints. Silky Brown-top     Eulalia aurea Grows in pure open Seed fill is often poor. Established plants will Poor seedling survival, stands. Timing of Good seed germinates persist, but only at wet but may find use at harvest is important readily. Most sites. wetter sites. because mature seeds seedlings die. drop rapidly. Cotton Panic     Digitaria brownii Seed is easily removed Seed does not Poor persistence. Establishment rate is from plants. Open germinate readily. very low. stands are uncommon. Most seedlings die. Woollybutt    Germination is too Eragrostis eriopoda Grows in pure open Seed is very difficult to No persistence difficult. stands. Seed often needs germinate. cleaning.

 Very Poor  Good  Poor  Excellent  Reasonable

DEPARTMENT OF LAND RESOURCE MANAGEMENT www.lrm.nt.gov.au

NATIVE PLANTS OF CENTRAL AUSTRALIA

ON THE PLAINS Trees Shrubs aneura Mulga Atriplex nummularia Old Man Saltbush Acacia estrophiolata Ironwood Callistemon Bottlebrush sp. Acacia kempeana Witchetty Bush Enchylaena tomentosa Ruby Saltbush Atalaya hemiglauca Whitewood maculata Spotted Fuchsia Corymbia opaca Bloodwood Melaleuca armillaris * Corymbia papuana Ghost Gum Melaleuca glomerata Inland Titree microtheca Coolibah Melaleuca linarifolia * striata Beefwood acuminatum Boobialla * eyreana Forkleaf Corkwood Senna artemisioides Silver Cassia Needlebush Hakea suberea Longleaf Corkwood RIVERINE (WATER ACCUMULATION) Trees Shrubs Eucalyptus camaldulensis River Red Gum Atriplex nummularia Old Man Saltbush (See Picture 4) Dodonaea viscosa Sticky Hop Bush Eucalyptus microtheca Coolibah Grevillea winpara * * Shrubs Senna artemisioides Silver Cassia Melaleuca bracteate Black Titree Vitex purpurea * Melaleuca glomerate Inland Titree

ROCKY GROUND OR ROCKY SLOPES PLANTS FOR SCREENS AND Trees WINDBREAKS Mulga Trees Acacia kempeana Witchetty Bush Acacia aneura Mulga Acacia pendula * Acacia kempeana Witchetty Bush Atalaya hemiglauca Whitewood Acacia ligulata Umbrella Bush Acacia salicina Cooba Corymbia opaca Bloodwood Allocasuarina River Sheoak * Corymbia papuana Ghost Gum cunninghamiana Eucalyptus gillenii Mallee Red Gum Eucalyptus mannensis Eucalyptus orbifolia Round- Mallee Eucalyptus orbifolia Round-leaf Mallee Eucalyptus sessilis Finke River Mallee Eucalyptus oxymitra Sharp-capped Mallee Eucalyptus trivalvis Victoria Spring Mallee Eucalyptus sessilis Finke River Mallee Silky Oak * * Not native to Central Australia Shrubs Shrubs Acacia holosercea * Capparis spinosa Acacia iteaphylla * var. nummularia Caper Bush Acacia retinodes * Eremophila freelingii Rock Fuchsia Atriplex nummularia Old Man Saltbush Gossypium sturtianum Sturts Desert Rose Eremophila sp. Fuchsias Senna artemisioides Silver Cassia Grevillea winpara * Grevillea olivacea * REASONABLY SALT TOLLERANT Melaleuca sp. PLANTS Myoporum insulare * Trees * Acacia ligulata Umbrella Bush Senna desolata Grey Cassia Acacia murrayana Colony Wattle Westringia sp. * Acacia pendula * Vitex purpurea Brachychiton gregorii Desert Kurrajong Eucalyptus gongylocarpa Marble Gum Eucalyptus intertexta Bastard Coolibah Eucalyptus gongylocarpa Marble Gum Eucalyptus intertexta Bastard Coolibah

DEPARTMENT OF LAND RESOURCE MANAGEMENT www.lrm.nt.gov.au