Module 6 Plants the others

Transcription

1 Module 6 Plants the others You have already studied the top plant bad boys in the previous two modules and now we will cover some more as it is important to know about these and be able to identify them. In this module we cover some others that you should be aware of, some of which are covered in the Wildlife and Countryside Act 1981 as species you cannot allow to escape into the wild. Go through this steadily; there are a lot of them! In some cases the species are actually planted in landscaping schemes for example... Cotoneaster Species Introduction Native to China, Tibet, Himalayas there are hundreds of species and hybrids of cotoneaster which have adapted to most soil types and most conditions. They are hardy evergreen, deciduous shrubs of various sizes from small prostrate shrubs to large tree-like shrubs. They spread through layering, suckers and by seeding. They do have their benefits including berries for birds and flowers for bees and insects. Case study Belfast city centre between Christmas and mid April 2001, 500 waxwings ate 500 berries each daily (twice their body weight), equals 25 million berries! So good for birds, but also spread by birds so can be invasive.

2 The different species and hybrids have varying sizes and shapes of leaves, and the plants themselves, but the key features are the berries and flowers and the woody stems. Control Strimming/Mowing/Flailing Suitable for small areas such as along paths, flat areas, and top of slopes but can be difficult and even dangerous in stony areas. This does control the plant in situ however, it does not kill the plant. Mowing may even encourage the spread of ground hugging runners and it may disturb fragile soils. Flailing is good for large areas and can control other invasive plants such as gorse or holm oak at same time. Hand Pulling Pulling is labour intensive and suitable for small areas only in areas that are unsuitable for machinery. It is good to pull shoots back to main root. This method may disturb fragile soil. Herbicide Only approved and appropriate herbicides can be used. If using herbicide next to water then the

3 Environment Agency s form WQM1 is required and only certain non-persistent chemicals can be used. Only properly trained people can use herbicides and there are health and safety issues around using chemicals. In addition it may not be appropriate to have herbicides on a site (e.g. on nature reserves with rare plant species present). Grazing The woody stems are not eaten by cattle and sheep although new growth may be when it is still soft. Goats can eat woody growth and can also cope with different terrain, and look after themselves, however, they can also easily escape. If fencing is required then is it common land? What would the cost, size of site, public access be if goats or fencing are used? Goats can also breed fairly prolifically and if left can end up with large numbers. Grazing Animal Project (GAP), PONT in Wales can give advice on using animals for controlling the species. Cherry laurel Prunus laurocerasus Introduction Originally from South East Europe and introduced into Britain in 1576 as an ornamental hedge plant. It is an evergreen shrub that grows to 6m high and suited to most soil types. It is often included in ornamental planting schemes. It produces dark shade which suppresses other flora and it is spread by seeds carried by birds. It is very similar to rhododendron for its treatment (see Module 4). Cherry laurel Prunus laurocerasus

4 Identification Leaves are evergreen, thick, waxy, leathery dark green leaves with a toothed edge and arranged alternatively, with stems ending in single leaf. Berries are red, then shiny black when ripe in autumn, similar to a grape in size and shape. Flowers form long spikes arising from the leaf node. Individual flowers are dull white, 8 mm across, 5- petalled flowers, which are sickly fragrant.

5 Flowers of Cherry Laurel Flowers in bud

6 Sea Buckthorn Hippophae sp Native to Eurasia and North America this large thorny shrub is widely planted and it is locally invasive. It is tolerant of salty conditions, and invades dunes and suppresses grassland communities. Absorbs nitrogen so improves soil. Identification Long silver haired, narrow alternative leaves. Orange berries in early autumn, good for birds. Deep roots and suckers. Sea buckthorn berries Control Physical removal by hand/ JCB. Or cut and treat stumps to prevent regrowth with herbicide such as Timbrel or Roundup. It is important to chip/burn cut material to prevent further spread. Butterfly Bush Buddleia davidii Introduction Originally from China, introduced about It is still widely planted as a nectar plant for butterflies. A

7 woody shrub that grows to around 3-4m. It prefers calcareous soils, waste ground, buildings and is commonly found on walls and quarries and what appears to be bare concrete! The plant is a prolific seeder and it can also regrow from cut stems. It creates heavy shade, damage to geological features and to buildings. Identification Leaves are dark green, downy (white below), oval-lanceolate, in opposite pairs and 19-25cm long. Stems are hollow and pithy, woody and fairly brittle.

8 Flowers are small in large cones in colours such as dark purple, mauve and white. Each flower has 4 petals and are tubular with an orange centre. Nectar-rich and highly attractive to butterflies. Control Cut and treat stumps with Roundup, picloram, or triclopyr. Cattle grazing in summer can also help as the new growth is soft. The rest of these species are mainly escapes and are not usually deliberately planted. Holm Oak/Evergreen Oak Quercus ilex Native to North Africa and the Mediterranean and is becoming dominant in some woodlands in the south of the UK and is able to withstand salt exposure and coastal locations. It grows to 20m. Identification Leaves are leathery, dark grey-brown, serrated with a holly-like appearance and acorns are in small velvety cups. Control Cut and treat stumps with herbicide to prevent re-growth.

9 Hottentot fig Carpobrotus edulis Originally from South Africa, it was introduced in the early 17 th century as an ornamental plant. The first wild record was in Now listed under Schedule 9 of the Wildlife and Countryside Act 1981 (as amended) as a plant that is not allowed to be released into the wild (see ). It spreads vegetatively, forming thick low mats which suppress native plants. They are mainly found on sea cliffs and dunes and are tolerant of salty and windy conditions. Identification Leaves are in pairs and fleshy with a triangular cross section and yellow/green, turning redder when older. Flowers are large and yellow to pink appearing in May/June. Control Treated by hand pulling or herbicides but this can lead to erosion if re-vegetation is not carried out, particularly on coastal cliffs.

10 Flowers start yellow and fade to pale pink

11 Fleshy triangular leaves. Cordgrass Spartina anglica

12 Introduction First recorded in Poole Harbour in the 1870 s, it arose when the European native cordgrass Spartina maritima (Small Cordgrass) hybridised with the introduced American Spartina alterniflora (Smooth Cordgrass). Spartina anglica was at first seen as a valuable new species for coastal erosion control, its dense root systems binding coastal mud and the stems increasing silt deposition, thereby assisting in land reclamation from the sea. As a result, it was widely planted at coastal sites throughout the British Isles, and has colonised large areas of tidal mudflats, eventually becoming an invasive species. New colonies may take some time to become established, but once they do, vegetative spread by rhizomes is rapid, smothering natural ecosystems and preventing birds like waders from feeding. Identification It is a herbaceous perennial plant growing m tall, yellowish green in spring and summer, and

13 turning light brown in autumn and winter. The leaves are 20-60cm long, and 1.5cm broad at the base, tapering to a point. It produces flowers and seeds on only one side of the stalk. The flowers are a yellowish-green, turning brown by the winter. Control Physical removal ensuring that rhizomes are also removed, or herbicide. In some areas however, a natural dieback of unknown cause has reversed the spread, and artificial control is no longer necessary where this dieback has occurred. Swansea Bay SSSI 2006 area covered was m², by 2008, after treatment, the area covered was m². This next section covers some nightmare water weeds that cause problems with choking up waterways and clogging drains and sluices, not to mention smothering the other life in the waterway. If using herbicides near water then you need to follow guidance from and apply for permission from the Environment Agency see Australian Swamp Stonecrop ( Crassula Helmsii) Introduction Also known as New Zealand Pygmy Weed it was introduced in UK in 1911 from Tasmania, it was first sold as an oxygenating plant in 1927, with the first wild record in 1956 in Essex. Now listed under Schedule 9 of the Wildlife and Countryside Act 1981 (as amended) as a plant that is not allowed to be released into the wild (see and Schedule 9 ). It prefers static or slow moving water such as ponds, lakes and canals, usually less than 3m deep. It tolerates most water chemistry, and even damp ground. It grows all year and can soon choke up water bodies. It takes up nutrients, and out-competes other plants, it reduces O2 which affects fish. It creates a thick blanket creating a poorer environment for fish etc. It is also shade tolerant, frost tolerant and desiccation tolerant. It has spread via aquatic plant sales often as a stowaway and from April 2014 it will be banned for sale in the UK. Identification Forms a light green blanket on the surface of ponds and other water bodies, or a tussock or blanket on damp ground. Flowers are small and white, June to September, about 1cm across, leaves are small and succulent. The plant may be emergent, submerged or terrestrial.

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16 Control Non Chemical DO NOT PRACTICE MECHANICAL CONTROL ON THIS PLANT. The fragments that are produced by cutting and tearing can regrow and spread the infestation downstream or re-infest the treated area. Fragments as small as one node (5mm) can regrow. On the ground it can be covered with sheeting for minimum of 3 months, but 6 months is better. Dredging can be carried out in shallow water and then material can be composted and either covered with soil or sheets or sprayed with herbicide. A drastic option is to drain the water body. Although this would effect any other life in the water body such as invertebrates and fish. Contact Environment Agency (EA) if you need to dispose of it off site. Chemical AFTER MARCH 2010 NO HERBICIDES CAN BE USED TO CONTROL SUBMERGED WEEDS C. helmsii is only really susceptible to herbicide formulations containing diquat and glyphosate. Diquat has been withdrawn from aquatic use by the EU, but the products are the subject of appeals to reinstate their use on this species. Glyphosate can be used on emergent vegetation (water or bank) in spring/summer with permission from Environment Agency. Repeat twice each year if needed. If possible remove all dead and treated material. Establish where re-infestations came from and maybe treat those also. Mechanical removal of dead plant material which has been treated with herbicides is recommended to reduce oxygen depletion by decomposing plant material. Other Grass carp may eat small amounts (EA) Parrot s feather ( Myriophyllum aquaticum) Introduction Originally from S America it was first found in the wild in the UK in 1960, Now listed under Schedule 9 of the Wildlife and Countryside Act 1981 (as amended) as a plant that is not allowed to be released into the wild (see ). It is spread via aquatic plant sales often as a stowaway and likes to live in static or slow moving water, damp ground, and dried out ponds. It prefers nutrient rich water, and survives winters. It causes flooding by blocking watercourses and drainage channels and can rapidly dominate a water

17 body displacing native species by forming a thick blanket, and thus creating a poorer environment for fish etc. Only female plants occur in UK so it spreads vegetatively from small pieces. Identification Shoots are both emergent and submerged appearing feathery when emergent. The plant is light green in colour with robust stems and leaves in whorls of 4-6. Control Chemical Chemical control can be achieved by applying herbicides in spring to shallow water and areas of damp ground. Glyphosate can be used, but is less effective than other herbicides but is safe around water (consult with EA first). Regular annual treatment is necessary and at least two applications per year. Spot treatment of small patches will prevent complete dominance. Treat regularly and early. Non chemical Do not allow broken pieces to remain in water. Cut material must be removed from the water as soon as possible and all fragments need to be removed to prevent regrowth and spreading downstream. Material should be cut as often as necessary and at least every 6 9 weeks from March to October to weaken the plant. Dredging will remove the plant very effectively from shallow areas, whilst careful pulling out of stems by hand after mechanical removal will help eradicate it.

18 Floating pennywort ( Hydrocotyle ranunculoides) Introduction From N America in 1980 s, found in the wild by It is found in slow, eutrophic water and over winters in margins and on banks. Now listed under Schedule 9 of the Wildlife and Countryside Act 1981 (as amended) as a plant that is not allowed to be released into the wild (see ). Reproduction is vegetative with some evidence of seed spread, it grows rapidly forming thick mats. It can grow up to 15m annually, or 20cm day, doubling its weight in 3 days with maximum growth during late summer. Identification Leaves are fleshy, circular to kidney shaped, to 180mm wide on emergence on stalks from horizontal stems. Stems are also fleshy with hair roots at 40-60cm intervals and form a thick mat of roots and stems to 0.5m below surface

19 Control Non chemical Cutting, dragging out or dredging is effective for large areas when it forms dense mats. Small areas can be hand pulled. Unfortunately removed material does not rot down well. Grazing by cattle on emergent stems can work but there is a danger to stock.

20 Chemical Glyphosate can be used on emergent growth (check with EA first) and repeated on regrowth. Water fern ( Azolla filiculoides) Introduction From North America, the only floating fern in Britain. Now listed under Schedule 9 of the Wildlife and Countryside Act 1981 (as amended) as a plant that is not allowed to be released into the wild (see ). Identification Small green floating fern with a reddish tinge but can be completely red in winter or when stressed (eg cold temperatures and shading). Grows vegetatively and by spores and forms dense mats especially when blown by winds or currents. These mats are a danger to stock and people because they look like

21 grass or solid ground and animals and people try to walk on it! When dense it blocks drains, filters etc and casts dense shade and reduces 02 so that other water plants as well as invertebrates and fish are badly affected.

22 Control Non chemical Can be collected by buckets and floating rope and netting works in small areas. However, it is hard to remove every fragment so re-infestation is common. Natural control Grass carp can clear small areas (EA) and there is now a weevil Stenopelmus rufinasus will control it which is available from This method can be used without licence as the weevil is species specific. It is also very effective and much more selective than chemicals. If spores have already been released then annual control will be required. Chemical Glyphosate can be used (seek advice from EA) to floating plants. Terbutyn granules (as Clarosan1FG) can be added to water but both of these will affect other plants. Both are most effective before complete infestation and if spores have already been released annual control required. Canadian waterweed / Curly waterweed / Nuttall s waterweed Elodea canadensis / Lagorosiphon major/ Elodea nuttallii Introduction Similar species sold as an oxygenator for ponds. Each is perennial and grow to 2-3m and are submerged. They spread vegetatively. Identification between them is difficult and can be grouped together as Canadian Pondweed. Curly waterweed is now listed under Schedule 9 of the Wildlife and Countryside Act 1981 (as amended) as a plant that is not allowed to be released into the wild (see ). Canadian waterweed First found in the wild in Ireland in 1836 and the rest of Britain in It is perennial and submerged and grows to 3m. Leaves are pointed or rounded, 2cm long, widest in middle in whorls of 3 with minute teeth

23 Curly waterweed Originally from South Africa, first found in the wild in Bedfordshire in 1944, and now widespread. A perennial and submerged growing to 3m. Leaves blunt and strongly curved, spirally arranged on lower parts. Tiny flowers. Nuttall s waterweed

24 Naturalised since Perennial, submerged, to 3m. Prefers more nutrient rich water Leaves - Pointed, widest at base, up to 3.5cm in whorls of 3 or 4, narrow, twisted and curved back. Tiny white flowers. Control Treatment for all is regular cutting, thinning or uprooting. When weed is dragged out of a pond or waterway it should be left on the side for a day to allow invertebrates to escape back into the water. And finally a seaweed... Wireweed/Japweed/Japanese Seaweed ( Sargassum muticum) Introduction Originally from the Pacific it was first noticed in the Isle of Wight in It was thought to have originated from ship ballast tanks (they take on seawater in one part of the world and discharge it before taking on cargo in another part of the world). Listed under Schedule 9 of the Wildlife and Countryside Act 1981 (as amended) as a plant that is not allowed to be released into the wild (see ). It is now widespread on the UK s south coast and the west coasts of Wales and Scotland, and around Ireland. Globally it it widely found across the whole of the west coast of North America and the western coasts of Europe.

25 Japweed in the water (foreground) Identification Large olive/brown seaweed (1m+), with regularly alternating branches with flat oval blades and small spherical bladders giving it a washing on line appearance.

26 It is often found free-floating, thus enabling spread, but it generally grows on hard surfaces up to 5m long. It is a perennial, dies back in winter leaving a holdfast. Control Remove ALL material, scrape off holdfast and compost it. Put filters on ship ballast tanks to prevent its spread. That is the end of this module. In Module 7 we will look at the World s Top 10 Most Invasive Species!