Part 3 Delivery to Site

RECOMMENDATIONS FOR PLANT HANDLING – FROM DELIVERY TO SITE TO SUCCESSFUL ESTABLISHMENT

1.0 INTRODUCTION

1.1 Plants are living things, even when dormant and transplanting and establishment involves them in considerable stress. If the process is to be successful it must be planned, managed and supervised to satisfy the basic biological requirements of the plants. To achieve this, the planting must be followed by a period of planned aftercare, covering at least two growing seasons.

These recommendations set out the requirements that should be followed and specified in detail according to the situation on each particular site. They assume that the nurseryman supplying the stock has adhered to the “Recommendations for Plant Handling from Lifting until Dispatch” and the purchaser has specified, and the nurseryman has adhered to, the “Specification for Packaging and Transporting Nursery Stock”. It is also assumed that the species and plant specification (age, size, etc) are correctly chosen for the geographical location and site conditions.

1.2 External Pressures

Even when the work is properly specified, there are many outside pressures that provide strong incentives to set aside or compromise the biological and other principles and factors. These include:-

The relatively short lifting and planting season for open grown plants
The logistics of lifting and supplying large numbers of different species
The financial pressure to complete projects as a whole, or within a financial year or complete deliveries in time for early payment.
The unpredictable and often unsuitable weather conditions which may reduce the effective planting season.
Engineering and building contractors not making the site available on time.

1.3 Management Measures

In order to counter these pressures, it is essential that:

The planting specifications are prepared in detail to suit the requirements of the site.
The planting is planned, as far as possible in advance of the planting season and plants are ordered, in the normally available sizes. (For guidance see National Plant Specification).
The planting area is adequately prepared when soil conditions are suitable, preferably in advance of the actual planting.
Arrangements are made for close liaison with the nurseryman during the planting season so that the supply of plants can be co-ordinated with the planting on site.
Adequate facilities are available for the receipt and storage of plants, including a conveniently situated water supply.
The receipt and care of the plants and the planting is only carried out by appropriately skilled operatives under the control of competent management and with adequate supervision.
After care is properly specified in advance and the finance secured as part of the overall planting and establishment cost.

2.0 PLANTING SEASON

2.1 Bare Root or Root-balled Plants

The natural planting season is during the dormant period which is normally from mid October to the end of March, but early planting, before the end of the year, is generally more successful than planting from January onwards. Late plantings are particularly vulnerable to Spring droughts and should be avoided unless watering can be carried out, or planting can be done with cold stored plants. Evergreens establish more readily if planted in early Autumn or late Spring, provided water can be applied in dry spells of weather.

In exceptional circumstances, where there is serious risk of frost lift, autumn planting is not recommended. In such circumstances it is preferable to plant as soon as the soil becomes workable in the Spring.

2.2 Container-grown Plants

These may be planted throughout the year in appropriate weather conditions provided they are regularly watered.

3.0 RECEIPT AND UNLOADING

3.1 When placing an order, the purchaser shall give the nurseryman notice of any restrictions of access to the delivery site, and notify him whether mechanical lifting aids are available for off-loading.

3.2 The nurseryman shall give adequate notice of the date and time of delivery within the agreed programme, and the purchaser shall ensure that adequate numbers of staff with mechanical lifting aids, where previously notified, are available to assist the off-loading without delay.

3.3 During unloading damage in handling shall be avoided.

3.4 The purchaser shall inspect and check the plants as quickly as possible after unloading to ensure each requirement has been complied with by the supplier. Whenever possible the deliveries should be planned so that the plants can be planted as soon as possible. If this is not possible the plants shall be moved in to temporary storage.

4.0 TEMPORARY STORAGE ON SITE

4.1 Short Term

Where the daytime air temperature is under 10°C plants may be stored in their packaging, under cover and away from sunlight, for a maximum of 7 days after receipt from the nurseryman but this may be extended to 14 days if temperatures are under 5°C. During this time the roots must be kept moist.

4.2 Longer Storage

4.2.1 Bare Root Plants and Root-Wrapped Plants

Bare root plants and plants root-wrapped in porous material should be heeled-in or plunged into moisture retentive material. Any non-porous root wrappings shall be removed before heeling in.

The roots of all plants shall be moist and placed so that all are in contact with the plunge medium. In order to achieve this, a free moving medium is required, such as a 50/50 mixture of course sand and peat, or sawdust, and care must be taken to ensure no degradation or heating up of the material. Bundles of plants will require cutting open and spreading out so that intimate contact between the roots and the plunging medium is achieved.

The plunging site shall be well drained and sheltered, and stout rails will be needed to support standard trees and other large stock. An adequate supply of water points is essential and the plunge medium must be kept moist at all times.

If necessary, plants may remain heeled-in from November to mid March, but the period shall be kept as short as possible. Beyond this period, plants required for late plantings shall be kept in cold store. Any other plants shall be planted out in nursery beds for a further season or containerised prior to the start of new growth.

4.2.2 Root-balled Plants in Porous Material

Root-balled plants in porous material shall be supported upright with the ball immersed in a deep layer of moist straw, hay, sand, peat, pulverised bark, sawdust, soil or other suitable material. Watering may be essential to prevent the ball drying out.

4.2.3 Container-grown Plants

Containers shall be kept upright on well-drained, weed-free ground. Sufficient watering will be required for container grown stock at any time of the year to prevent the compost drying out. Tall plants will require support to prevent them blowing over. Species susceptible to frost damage shall be given temporary protection. (See also Part I para. 5.3).

4.3 Removal from Temporary Storage

Container grown stock and root-balled plants shall be well watered before transportation to the planting site. The roots of bare-root stock shall be moist before removal from the heeling-in or plunge medium and the roots shall be placed directly into black polythene bags to prevent drying-out and kept in them until immediately before planting. Consignments supplied in bulk shall be split up and wrapped in black polythene bags to minimise the length of time plants are exposed to drying during the planting process. (The use of co-extruded black and white polythene bags is recommended. See Part II 1.3). Plants shall be re-labelled as necessary.

5.0 GROUND PREPARATION

5.1 The planting site shall:-

5.1.1 Be naturally or physically drained, or raise by mounding so that the plants will not be subjected to waterlogging at any time.

5.1.2 Have a soil texture and structure that will retain and release moisture and nutrients to the plant and a crumb structure that will promote root growth to at least 3 times the width and 1.5 times the depth of the roots of the plants to be planted.

5.2 Preparation of the Planting Site

The following are essential points that should be considered and specified as necessary if these properties are to be achieved:

5.2.1 Any ground preparation is best carried out in advance of the planting season, when the weather is more reliable and less soil structure damage is likely to be caused. This will allow more time for the planting operations but it is essential to ensure that the soil is protected from construction traffic or other compaction or pollution.

5.2.2 Extremely heavy and poorly structured soils may need to be improved by the thorough incorporation of suitable organic matter and special drainage arrangements. Extremely light soils may also need added organic matter to improve their water holding capacity and avoid the need for frequent irrigation. (Peat based composts or similar are not suitable for these purposes).

Where planting is proposed on imported soil or made up ground or where the soil structure has been impaired, a good soil structure needs to be established before planting takes place. This may involve deep soil cultivation and draining, followed by grassing or herbaceous cover, and the delay of planting for at least one growing season.

5.3 If ground preparation as specified in 5.2 is necessary it shall be carried out over an area at least 3 times the diameter of the root spread, and 1.5 times the depth of the roots, of the plants to be planted.

6.0 PLANTING

6.1 Soil Conditions for Planting

At the time of planting, the soil shall be moist and friable and not frozen, excessively dry, or water-logged.

6.2 Planting Requirements

The excavated hole shall be of sufficient size to accommodate the spread roots and the stock shall be planted so that after any settlement it is at the same depth as it was grown in the nursery. If the sides of the planting hole become smeared during digging, particularly on heavy clay soils, the smearing shall be broken up before planting.

6.3 Stabilising Support and Protection

Most plants above 1m high will need a support to hold them secure at ground level either by stakes or by cables for very large stock. Stakes or stout canes as specified, shall be inserted before planting. Plants shall be held secure against the stake by the use of a proprietary tie, or similar method, ensuring that the stem shall not chafe against the stake and there is space for stem expansion. Short stakes to hold the base of the stem are preferable but individual guards or shelters may be needed to protect trees against physical damage by vandals, cattle, rabbits, mowers or strimmers. Alternatively, the plantation may be protected by suitable fencing. See also 7.5.

6.4 Treatment of Plants immediately Prior to Planting

Bare root plants shall be kept in polythene bags until immediately before planting. They shall be kept out of direct sunlight unless co-extruded bags are used. Similarly all containers and wrapping, unless fully bio-degradable, shall be removed at the latest point before planting.

Root-balled plants and plants in root control bags shall be placed in the planting pit before the hessian or other protective material is removed to avoid disturbance of the root-ball. Wire netting shall be left on the root ball provided that there is only biodegradable porous material between the wire netting and the root-ball. Root control bags should be removed.

Damaged or torn roots and stems shall be cut back cleanly with a knife or secateurs and, particularly with container-grown plants, any coiled roots shall be spread out or cut to prevent future stability problems.

6.5 Back-filling

During backfilling around the plant, the soil shall be lightly firmed to ensure intimate contact with the roots, but with large material, successive layers of soil will need to be firmed as backfilling proceeds. The layers of soil shall be firmed separately so that the plant is securely held but penetration of moisture is not restricted. Snow must not be allowed to become mixed with the backfill material.

Plastic perforated pipe for irrigation should be installed as part of the back filling, where specified. (see 7.4 below).

6.6 Pruning

After planting, any damaged, dead, diseased or crossing branches shall be removed by pruning.

Opinions differ on whether the size of the head of a standard tree should be reduced after planting, but if it is decided to do so, do not prune the central leader if it is intended that the tree should grow to full stature. (see BSI 3936 Part I Appendix Table 4 for guidance).

7.0 AFTER-CARE

7.1 Firming after Frost or Wind

If the roots of newly planted plants are loosened, they shall be re-firmed as soon as practicable. This is readily achieved with the toe of the boot, to exclude air pockets from around the roots and particularly next to the base of the stem.

7.2 Weed Control

Weeds and grass compete for moisture and nutrients and shall be eliminated until the plants are well established; usually for at least 2 years. Cutting or mowing weeds does not prevent this competition. Pre-planting site preparation may give a weed-free start. A minimum of a one metre diameter weed-free area shall be maintained around each transplant, by herbicide applications, mulches or hoeing throughout the whole of the first two years. Larger weed-free areas are appropriate for larger plants and should at least cover the surface of the original planting pit.

Mechanical strimmers and mowers must not be used near the stems of the plants as they can seriously damage the bark.

7.3 Conserving Moisture

Mulching may be used to conserve soil moisture. Mulches achieve this by helping to control weeds which rapidly transpire moisture, and by reducing evaporation from the soil. Mulches may consist of either sheet materials such as ultra-violet stabilised polythene, roofing felt; or granular materials like pea gravel, ground bark or wood chippings. Mulches shall only be applied when the soil is moist. Regular hoeing in dry weather will produce a dust mulch.

7.4 Providing Moisture

Though local climate and soil types will vary the requirements, as a guide it is recommended that during the growing season, newly planted trees and shrubs 31666 Glossary 10.2 (22) 27/2/02 11:31 am Page 20.shall be irrigated following any four week period without appreciable rainfall. This may not apply to forestry planting but is particularly important for amenity trees in harsh urban or exposed positions.

For reasonable growth, irrigation shall be applied at fortnightly intervals to moisten the soil so that the full rooting depth of soil is saturated. The amount of water required will vary considerably according to the texture and structure of the soil but as a guide a heavy standard tree will require at least 20 litres and a small transplant approximately 10 litres for each watering. Soils with low water holding capacity will only need smaller amounts of water but with irrigation carried out more frequently.

Container grown stock using soil-less compost may require more frequent watering in the early stages as once the compost dries out it can be very difficult to re-wet.

Water must always be applied so that the soil is moistened to the depth of the root zone. For large nursery stock this can be facilitated by installing lengths of perforated plastic drainage pipe, or similar devices, in the planting pit at the time of planting.

Overwatering is wasteful, both of water and other resources, and will only serve to leach nutrients away from the soil.

7.5 Protection

Plants may be damaged by voles, mice, hares, rabbits, deer, farm stock and vandals and suitable protection shall be considered at the planning stage. Regular inspections, say once a month, are essential so that appropriate action may be taken. Local circumstances will dictate whether it is best to fence a large area, use individual guards, or use poison for rodents. Maliciously damaged plants shall be replaced as soon as possible.

7.6 Stake Maintenance

Stakes and ties must be maintained to prevent damage to trees. Stakes shall be inspected regularly to ensure they remain secure and ties shall be adjusted at least once a year to ensure they are not cutting into the stem. As soon as they are no longer necessary, stakes shall be removed to encourage the trees to develop naturally. This should normally be up to 3 years after planting.

Plant sizes and specification	BS 3936 Part I 1992
Choice of species	Trees and Shrubs for Landscape Planting (JCLI Recommended Plant List)
Contracts for Plant Supply	CPSE Recommended Standard Form of Tender for the Supply and Delivery of Plants
Statutory Regulations	Plant Health (Great Britain) Order 1993
	EEC Forest Reproductive Material Regulations 1977

No. 97-91-ARB	Amenity Tree Planting with Bare-Root Stock
8-79-ARB	Damage to Broadleaved Seedlings by Desiccation
75-88-ARB	Alginure Root Dip and Tree Establishment
64-86-SILN	Rough Handling Reduces the Viability of Planting Stock
98-91-ARB	Cell Grown Broadleaved Stock
110-87-SILN	The use of Co-extruded Polythene Bags for Handling Bare-Rooted Planting
Available from:-	Arboricultural Advisory and Information Service Forest Research Station Alice Holt Lodge Wrecclesham Farnham Surrey GU10 4LH