ELCOT ENVIRONMENTAL Japanese Knotweed Removal Specialists Since 1982 1
JANUARY TO MARCH Typical Japanese Knotweed Appearance Skyline views of typical Knotweed stems showing desiccated flower sets. 2 Picture 1b Picture 1a
JANUARY to MARCH 3 No visible sign of any “green” stalks – only previous season’s dead brown stems invariably broken, due to wind damage. Picture 1c Picture 1d
JANUARY to MARCH 4 • Possibility of a few new emerging K Old stalks tend to break off leaving a Knotweed shoots may be visible, short stump connected to the “crown”, depending on weather conditions. site of re-emergence for the new seasons growth. • “Red blunt “growth tips” just visible through the previous season’s leaf and stem litter. Picture 1e Picture 1f
APRIL to JUNE 5 New Japanese Knotweed New stem extension starts and is shoot emergence “red to dark very rapid +/- 50cm/week on a green” in colour. well established Knotweed stand. Picture 2a Picture 2b
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APRIL to JUNE 7 Both photo’s show this rapid stem extension – this is about 3-4 weeks growth. Knotweed can reach upwards of 3.5 metres in height in a single growing season. Picture 2c Picture 2d
APRIL to JUNE 8 By the end of June the stand is well over 2.5 – 3 metres tall and is densely covered in medium to large yellowy green leaves. The stand at this stage is very difficult to penetrate and some larger area stands require several spray treatments to obtain a satisfactory result. Picture 2e Picture 2f
JULY to SEPTEMBER 9 Well established stand growing around the edge of a car park. Dense full leave cover, making it very difficult to penetrate physically and/or with chemicals. Picture 3b Picture 3a
JULY to SEPTEMBER 10 Smaller shoots can also be found at this time of White flowering stage. the year, depending on, or subjected to any previous disturbance. Picture 3c Picture 3d
JULY to SEPTEMBER 11 The flowering stage can spill over to October/November. Small creamy white flowers which hang in clusters from the leaf axils (where the leaf joins the stem). Picture 3e Picture 3f
OCTOBER to DECEMBER 12 Leaves start to turn a dull green colour at this time of the year coupled with the brown remnants of the flowers. The plant is very drab. Picture 4a Picture 4b
OCTOBER to DECEMBER 13 The leaves start to turn yellow as the season progresses and the plant shuts down for Winter. This may vary depending on the location and surrounding temperature of the stand. Picture 4c Picture 4d
OCTOBER to DECEMBER 14 Until finally turning brown and shedding, leaving brown stalks with the remnants of dried up flower buds still visible on the ends of the stems. Picture 4e Picture 4f
DISTURBED KNOTWEED 15 Emerging Knotweed with small clustered leaves New “Red” shoots and first pair of leaves sign of previous chemical treatment. emerging from disturbed ground. Picture 5b Picture 5a
DISTURBED KNOTWEED 16 Previously treated Knotweed against a building Emerging Knotweed shoots bent/twisted – sign of showing stunted growth. past chemical treatment. Picture 5c Picture 5d
DISTURBED KNOTWEED 17 Knotweed shoots emerging from disturbed Vehicular access showing stunted growth ground near newly installed works. compared to that off the path. Picture 5e Picture 5f
DISTURBED KNOTWEED 18 New growth as a result of previous “Roundup” New growth emerging from previously treated treatment Knotweed Picture 5g Picture 5h
DISTURBED KNOTWEED 19 Stem extension of Knotweed growing up Sprouting Knotweed shoots emerging from a through disturbed ground, after cutting back. disturbed and gravelled area. Picture 5j Picture 5i
OTHER PLANTS MISTAKEN FOR JAPANESE KNOTWEED 20 Polygonatum (Fallopia) baldschuanicum (Russian Vine) A rampant climber with stems up to 12m long. Flowers white to pink tinged. Leaves ovate or heart-shaped, pale green. Picture 6a
OTHER PLANTS MISTAKEN FOR JAPANESE KNOTWEED 21 Arum maculatum/italicum (Lords & Ladies Cuckoo Spit) The purplish cylindrical flower- head is enclosed within a greenish yellow swathe and sometimes spotted with purple. It gives off a smell of decay along with its slight heat, attracts flies. The long stalked leaves are shaped like arrowheads and often have dark spots. The poisonous berries can be fatal if eaten by children. Picture 6b
OTHER INVASIVE PLANTS 22 Himalayan Balsam (Impatiens Glandulifera) Introduced to the U.K. In 1839, it is now rapidly spreading along riverbanks and other areas of damp ground. It produces purplish-pink through to white helmet shaped flowers. These are followed by seed pods which, when ripe, explode scattering up to 800 seeds. The seeds can remain viable for about 2 years and germinate between February and March. Picture 6c
OTHER INVASIVE PLANTS 23 Non-native Cotoneaster ( Cotoneaster spp. ) AVOIDING OFFENCES Some Cotoneaster species are non-native and invasive • A method statement is required for works affecting plant species in the UK, and they occur in a variety of areas of non-native Cotoneaster; habitats, • An ecologist should oversee the works to areas of non- including in woodland, scrub, hedgerows and quarries, native Cotoneaster; • Excavated material (to 1.5 m deep) of areas of non- roadsides, railways banks and waste ground. Cotoneaster species are often found in ornamental planting. native Cotoneaster should be loaded directly to a suitable Reproduction is by seed. Evidence from surveys suggests truck; that non-native Cotoneaster is present within the vicinity of • Disposal of non-native Cotoneaster material should be the proposed works. made to an approved landfill site; LEGISLATION • Clean all vehicles and equipment used in the Five species of non-native Cotoneasters are listed on Cotoneaster area; Schedule 9 of the Wildlife and Countryside Act 1981, which • Top soil brought into the site must be free of makes it an offence to plant or cause to grow (spread) Cotoneaster and other invasive species. these species in the wild. Anyone convicted of an offence under the above legislation may face a fine of £5,000 or six months’ imprisonment for a summary conviction or an unlimited fine or two years’ imprisonment on indictment. Inappropriate disposal of non-native Cotoneaster material may lead to prosecution under the Environmental Protection Act 1990. Picture 6d
OTHER INVASIVE PLANTS 24 Giant Hogweed (Heracieum Mantegazzianum) The Problem Giant Hogweed was first introduced to Britain in 1893 as an ornamental plant. It spread from gardens and now covers many areas of wasteland and riverbanks in the British Isles. By forming dense stands it can displace native plants and reduce wildlife interests. During winter when the plant has died back it leaves the area bare of vegetation and increasing the risk of erosion and re-colonisation from seeds washed downstream. Health It is essential that full protective clothing is worn when working near Giant Hogweed. Hairs on the outside of the stems and leaves, and poisonous sap on the inside can cause severe skin irritation. Blistering occurs 24-48 hours after initial contact and dense pigmentation is visible after 3-5 days. This may persist up to six years. Un-shaded habitats tend to produce plants with greater quantities of toxins due to the soil having a higher nitrate level. Legal It is an offence under section 14(2) of The Wildlife and Picture 6e Countryside Act 1981 to plant or otherwise cause to grow in the wild any plant listed in schedule 9, part 2. This includes Giant Hogweed.
OTHER INVASIVE PLANTS 25 Mare’s Tail (Equisetum) The Problem Horsetail or Mares tail (Equisetum) is a very invasive weed. It is a perennial weed which will grow in a wide variety of soils; Horsetail rhizomes can penetrate several metres below the soil surface. They thrive in poor soils but have no preference for soil type. It is appearing more and more on newly built environments pushing its way up through tarmac and appearing in landscape areas. When in a planted landscape area it becomes harder to treat with herbicide due to the close proximity of the “Mares Tail” “Mares Tail” growing up between paving Slabs growing in amongst the herbaceous plants etc., with the shrubs being more susceptible to the chemicals than the “Mares Tail” itself. Identification The Mares Tail family produce two types of stems: 1. A short brown stem like asparagus (15 to 45cm) emerges early in the year is coned shaped at the tip which contains large numbers of spores. 2. A taller dark green stem (up to 65cm) it is sterile and emerges after the first stems have died back they are bottle brush in appearance. These are rich in silica and have a tough, wiry feel to them. Pictures 6f / 6g / 6h (Summer) (Spring)
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