GB2411388A

GB2411388A - Plant protection system

Info

Publication number: GB2411388A
Application number: GB0502626A
Authority: GB
Inventors: Barry Sutton; James Hepburne Scott
Original assignee: ALBA TREES PLC
Current assignee: ALBA TREES PLC
Priority date: 2004-02-26
Filing date: 2005-02-09
Publication date: 2005-08-31
Anticipated expiration: 2025-02-09
Also published as: IE20050062A1; GB0404238D0; GB2411388B; GB0502626D0

Abstract

The present invention provides a method of protecting young growing plant seedlings 1 comprising the steps of: <SL> <LI>a) providing a fine mesh tubular net guard 7; and <LI>b) disposing the net guard around the seedling 1 so as to substantially enclose the root system and foliage portions 4,3. </SL> The invention also provides a protected seedling consisting essentially of a seedling 1 with a root system portion 4 consisting essentially of a root system 6, optionally embedded in a solid phase growth medium 5, and a fine mesh, resiliently expandable and/or flexible, tubular net guard 7. The net guard 7 is disposed around the seedling 1 in a partly expanded condition so as to enclose substantially the root system and foliage portions 4,3.

Description

2411 388

PLANT PROTECTION SYSTEM

The present invention relates to a plant protector system for providing protection against damage in transit to the planting site and/or damage from other harmful agents once planted. s

Plant protection against grazing animals is currently undertaken by the use of solid plastic tube guards or by the use of large aperture coarse mesh guards supplied as flat sheets which are rolled into a tube around the planted tree. Pre-formed tubular wide mesh guards are also available. In all cases the guard is applied to the plant after planting out thereof, usually requiring the fitting of additional supporting stakes or canes.

In many cases it becomes necessary to remove the protective structure after several years in order to prevent damage to the growing plant from the guard itself.

Plant protection against harmful insects, which can readily traverse such conventional guards to gain ready access to structures as described in the preceding paragraph, is currently undertaken separately by the use of chemicals or additional physical barriers. Chemicals can be difficult to apply effectively as well as giving rise to environmental hazards, and currently available physical barriers require regular maintenance to remain effective. Currently used chemical sprays and physical barriers only target the above-ground part of the plant.

It is an object of the present invention to avoid or minimise one or more of the above disadvantages.

In one aspect the present invention provides a method of protecting young growing plant seedlings comprising the steps of: a) providing a fine mesh, resiliently expandable and/or flexible, tubular net guard; and b) disposing said net guard around at least a root system portion of a seedling so as to substantially enclose at least said root system portion with said net guard.

In a preferred form of the invention, the method includes the further step of planting out said seedling with at least said root system portion thereof substantially enclosed in said net guard.

It will be appreciated that, in the context of the present invention, the root system portion of a seedling may be presented in various different forms, according to the requirements of the plant species, the nursery grower, the transporter, the planter, the customer, etc. It is generally preferred for many species of tree seedlings that these are raised initially in a container holding a body of growth medium in which the root system is substantially encased, and the seedling is removed from the container for planting out together with said body of growth medium, in order to minimize disturbance and any possible trauma to the roots. In such cases where the root system is encased in growth medium, the root system portion is generally referred to as a root plug. In other case though, in which the seedling is not grown in individual containers, a greater or lesser portion of the growth medium may be removed from the root system, prior to planting out.

The present invention can offer protection against damage of the roots in transit from nursery to planting site, and depending upon the guard configuration used, protection against insect attack (below or both above and below ground), protection against grazing animals, or a combination of all three, in a particularly simple and economic manner, without recourse to supplementary materials or labour and with little or no subsequent maintenance. Whilst the mesh may also provide a degree of protection from environmental extremes such as severe frost, high wind, intense solar radiation etc during the establishment phase of the plant, the mesh is sufficiently open to maintain an airflow around the contained plant thereby avoiding excessively damp and humid conditions.

Preferably the net guard is disposed so as to extend substantially up to the tip (of the foliage portion) of said seedling, preferably not more than 10 mm below the tip. On the other hand the net guard should not extend too far beyond the tip, as this may give rise to difficulties in the tip pushing open the upper end of the net guard and growing up out of the opening - especially when the end portion of the net guard projecting beyond the tip is bent over, as may occur in adverse weather conditions such as high winds. Desirably therefore the net guard should not project more than 10 mm beyond the tip of the seedling.

The high flexibility and, where applicable, resilient deformability of the mesh guard, will also provide minimal restraint to plant movement thereby promoting increased strength of the growing stem.

Moreover, by using a material, which will degrade gradually following planting out, the plant may be allowed to achieve free growth without the need for subsequent maintenance or removal.

Whilst it will be appreciated that very small mesh aperture sizes will be most effective in resisting penetration by small insect pests, these will tend to limit the degree of expandability of the tubing in the case of an expandable netting, whilst increasing the consumption of material used to manufacture the netting and its cost of production, and possibly restricting root penetration and development. It will also be understood that different geographical locations of use and/or different plant species, will often suffer from different pests and other hazards to the growing plants, and it will therefore generally be desirable to take these into account when choosing the optimum tubular netting for different locations. In general there may be used mesh apertures with a maximum dimension in the range from l to lOmm, preferably from 2 to 8mm, advantageously from 3 to 7mm. With a rhomboidal mesh aperture having a length of say sum, it will be appreciated that (with a resiliently expandable netting), whilst the width can increase up to around 5mm in the fully expanded condition of the tubular netting, in the unexpanded condition it can decrease to as little as l or 2mm.

Where resiliently expandable netting tubing is used in a net guard in accordance with the present invention, this helps ensure that the netting fits closely around the stem and foliage of the seedling as well as the root system portion thereof, minimizing the effective mesh aperture size of the net guard, so that the seedling is provided with maximum protection at a particularly vulnerable stage in its life, whilst minimising interference with future growth and development of the plant by allowing the netting tube to be readily expanded to accommodate growing foliage, and allowing ready penetration and opening out of mesh apertures by developing roots.

It will be appreciated that various kinds of netting tubing may be used in accordance with the present invention. In general there is used a combination of material and net construction, which permits a large degree of resilient expansion of the tubing (with an accompanying expansion of the effective mesh aperture size of the netting). Typically there would be used netting tubing having a ratio of fully expanded diameter to unexpanded diameter of at least 1.1:1, preferably at least 1. 5:1 conveniently from 1.1:1 to 3:1. Naturally, the diameter size range (unexpanded to expanded) of the netting tubing will be chosen so as to be appropriate to the seedling size. In general the diameter of the netting tube should be chosen so that the tube is only partly expanded to accommodate the seedling - generally so that it is expanded to not more than 70%, preferably not more than 50O, of its fully expanded diameter.

Typically the unexpanded diameter should be not greater than 90mm, preferably not greater than 60mm.

A variety of suitable netting materials, generally synthetic polymers such as polyalkenes, for example, LLDPE, HDPE, polypropylene etc. and copolymers such as LLDPE, EVA, are well known in the art, as are also, progressively degradable forms thereof, which are preferred, in order to avoid the need for subsequent removal of the net guards from the growing plants.

It will be appreciated that the rate of degradation of the material should generally be chosen so as to allow substantial maintenance of protection during the period when it is most required, without extending excessively beyond this. Typically in the case of tree seedlings, it is desirable that the material should be substantially degradable at from 24 months to 48 months.

Different forms of net construction may also be used including inter alla filaments with knotted or thermoformed intersections, as well as netting formed by other techniques such as expansion of perforated sheeting, as well as knitting and weaving, although the former are generally more convenient and/or more economical. It will also be understood that a wide range of grades and weights of netting materials may be used in the net guards of the invention. In general it is preferred to use lighter weight and more economical grades without however prejudicing sufficient robustness to withstand the application, planting-out and growth conditions. Typically there may be used netting tubing having a weight of 2 to Beg, preferably 5 to 25g, per linear metre for a 60mm (unexpanded) tubing.

Advantageously there is used a net construction with rhomboidal mesh apertures as these can facilitate net expansion.

Nevertheless other net construction geometries may also be used including nets with hexagonal mesh apertures, and nets with rectangular, conveniently square, mesh apertures.

The method of the invention may be used with a large variety of plants, although it will generally be most beneficial with tree seedlings and/or plants particularly susceptible to damage due to their nature and/or the hazards of transportation and/or the particular location in which they are to be planted out.

Conveniently the net guard is applied by supporting it in an opened out (and where applicable expanded) condition over a tubular support guide into which at least the root system portion of the seedling is fed, and the net guard together with the seedling advanced relative to the tube so that as the net guard disengages from the support guide, it more or less closely engages said root system portion (and where applicable the stem and foliage as well). In the case of an expandable net guard, it collapses into a substantially less expanded condition fitting closely around the seedling and its root system portion.

Advantageously there is used a continuous length of net guard tubing which is cut to length after it has been applied to the seedling.

The seedling inside the net guard is then immediately protected against pest and environmental hazards, while awaiting and during, transportation to a planting out location, as well as facilitating handling thereof and reducing damage to the foliage or roots and to the integrity of the root system portion, e.g. root plug, during handling thereof.

At the planting out site, the protected seedling is planted out in essentially the same manner as a seedling without such a net guard (inserting the root system portion into a suitably formed hole in the ground), but whilst leaving the net guard in position around the root system portion. Thus there is no need for any additional handling or procedures at this stage. In the case of a full length net guard full protection of the seedling above and below ground may thus be obtained immediately.

Nevertheless, if desired, it may be convenient to include some adjustment of the net guard above ground. Thus for example, the free end of an overlength net guard may be doubled back over the plant to provide a double layer of protection - as well as leaving an opening above the tip of the seedling, and the free end subsequently extended upwards as the plant height increases.

Providing such an opening above the tip of the seedling can be especially beneficial in the case of seedlings which can have difficulty in forcing themselves though the constricted neck portion of an expandable net guard.

In a further aspect the present invention provides a protected seedling consisting essentially of a seedling with a root system portion consisting essentially of a root system, optionally embedded in a solid phase growth medium, and a fine mesh, resiliently expandable and/or flexible, tubular net guard, said net guard being disposed around at least said root system portion with said net guard in a partly expanded condition so as to enclose substantially at least said root system portion.

Preferably the net guard extends beyond the base of the root system portion, and the free end of said net guard below the root system portion is substantially closed off. In the case where the bottom end of the net guard is closed off, the net guard may be dimensioned so as to be a more or less loose fit around the root system portion. Where it is not so positively closed off, however, it is generally desirable for the net guard to be dimensioned so as to grip the root system portion, e.g. root plug.

Further preferred features and advantages of the invention will appear from the following detailed description of a preferred embodiment, given by way of example, with reference to the accompanying drawings in which: Fig.l is a partly cut-away elevation of a seedling provided with a plant protection system according to the invention; Figs. 2 and 3 are schematic elevations of different configurations of plant protection system according to the invention; and Fig. 4 is a view similar to Fig. l of another embodiment.

Fig. l shows a tree seedling l comprising a stem 2 with foliage 3 and a root system portion in the form of a root plug 4 comprising a body of compost 5 encasing the root ball 6 of the seedling l. (It will be appreciated that part of the compost body has been omitted to reveal the root ball 6 which would actually be substantially encased by the compost). A tubular net guard 7 is disposed around the seedling l so that upper and lower ends 8, 9 thereof extend slightly above and below the tip lo of the seedling l and the base It of the root plug 4, respectively. - 9 -

The net guard 7 is made of a highly, resiliently, expandable netting so that in an unexpanded condition thereof - at the upper and lower ends 8, 9 the tubular net guard 7 has only a very small diameter and tends to close up more or less completely as the walls collapse against each other. The net guard 7 is however easily expanded by the foliage 3 and root plug 4 to accommodate these, without exerting undue pressure against them and substantially avoiding any damage thereto. The net guard is moreover restricted in length so as to project not more than about 10 mm beyond the tip 10 of the seedling, so that it remains erect and is substantially resistant to bending over and creating an obstruction or resistance to the seedling tip 10 pushing open the net guard upper end 8 and growing up out of it.

Furthermore the resilient nature of the net guard 7 ensures that it tends to fit closely around the various parts of the seedling 1, adopting a smaller diameter, less expanded, condition around the stem 2 below the foliage 3, as may readily be seen in the drawing.

Fig. 2 is a schematic view illustrating a configuration generally corresponding to the embodiment of Fig. 1.

Fig. 3 is a schematic view similar to that of Fig. 2 and shows another embodiment in which instead of using a resiliently expandable tubular netting material, there is used a substantially non-expandable flexible tubular netting material in the net guard 13. The net guard 13 is accordingly dimensioned so as to be a relatively close fit around the root plug 4 and a support stake 14 included alongside the seedling 1 with its root plug 4. The bottom end 15 of the tubular net guard 13 is closed off by heat sealing of the netting tube into a chisel point. The net guard 13 is also sufficiently long so that it can encase the seedling when doubled back over itself, and can subsequently be progressively extended upwardly as the seedling height increases with growth of the plant.

Fig. 4 shows a further embodiment in which the root system portion is in the form of a root ball 6 substantially free of any growth medium. In this case also it may be seen that the upper end 8 of the net guard 7 does not extend right up to the tip lo of the seedling l, in order to facilitate growth of the seedling foliage 3 up our of the net guard 7 and make it easier for the foliage to push the material of the net guard 7 aside and force it open. In this way the seedling is provided with reasonably extensive protection when it is at its smallest size, whilst also minimizing any possible restriction or interference with the growth of the seedling after planting out.

It will be appreciated that various modifications may be made to the above described embodiments without departing from the scope of the present invention. Thus, for example, instead of using heat sealing to close of the bottom end 15 of the netting tube, there could be used a metal clip or staple l6 crimped around the bottom end l5 (see Fig. 2).

It will also be appreciated that whereas the net guard upper end 8 is shown to extend to just above the seedling tip lo in the Fig. l embodiment and just below it in the Fig. 4 embodiment, the reverse arrangements could equally well be used.

Claims

1. A method of protecting young growing plant seedlings comprising the steps of: a) providing a fine mesh, resiliently expandable and/or flexible, tubular net guard; and b) disposing said net guard around said seedling so as to substantially enclose the root system and foliage portions thereof, with said net guard.

2. A method according to claim l in which said net guard is disposed so as to extend substantially up to the tip of said seedling.

3. A method according to claim l or claim 2 in which said net guard is disposed so as to extend not more than lOmm beyond the tip of said seedling.

4. A method according to claim 3 in which said net guard is disposed so as to extend substantially beyond the lower end of the root system portion of said seedling.

5. A method according to any preceding claim, in which the root system of the seedling is substantially free of growth medium.

6. A method according to any one of claims l to 4, in which the root system of the seedling is substantially encased in growth medium.

7. A method according to claim 6 in which said root system portion is in the form of a root plug.

8. A protected seedling consisting essentially of a seedling with a foliage portion and a root system portion consisting essentially of a root system, and a fine mesh, resiliently expandable and/or flexible, tubular net guard, said net guard being disposed around said seedling with said net guard in a partly expanded condition so as to enclose substantially said root system and foliage portions. s

9. A seedling according to claim 8 wherein said root system is embedded in a solid phase growth medium.

10. A seedling according to claim 8 or claim 9 wherein is used a mesh of a synthetic polymer.

11. A seedling according to any one of claims 8 to 10 wherein is used a mesh of a biodegradable polymer.

12. A seedling according to any one of claims 8 to 11 wherein is used a mesh having a rhomboidal mesh aperture.

13. A seedling according to any one of claims 8 to 12 wherein is used a mesh having a mesh aperture with a maximum dimension of from 1 to 10 mm.

14. A seedling according to any one of claims 8 to 13 wherein is used a mesh having a weight corresponding to a weight of 2 to 30 g per linear metre for a 60 mm (unexpanded) tubing.

15. A seedling according to any one of claims 8 to 14 wherein is used a mesh netting tubing having a ratio of fully expanded diameter to unexpanded diameter of at least 1.1:1.

16. A seedling according to claim 15 wherein said ratio is from 1.1:1 to 3:1.

17. A method of protecting young growing plant seedlings substantially as described hereinbefore with particular reference to any one of the accompanying drawings.

18. A protected seedling substantially as described hereinbefore with particular reference to any one of the accompanying drawings.