Moderate (erosion, wildlife, habitat)
Hoes are hand tools that have been used in agriculture for at least 4,000 years. As they have been in use for thousands of years and across numerous agricultural civilizations, a variety of hoe blades, handle types, and names for the tool have been developed. In general, a modern hoe consists of a wooden handle generally 4-6 feet long, and a wide flat metal blade that is perpendicular to the shaft. Usually the blade is rectangular in shape, although many different blade shapes have been developed, from triangular, to more rounded and heart-shaped, to long and thin, to ones where the blade has been divided into tines, like a fork hoe.
The grub hoe is the most commonly used hoe type for land managers. It is used to cut into the soil in order to cut weed roots below the soil surface. When pulling or lifting the shaft, it can also be used to turn over the soil around a weed, uplifting some of its roots. A grub hoe is operated by lifting the shaft and swinging the blade into the ground, so the blade penetrates the soil and severs weed roots or stems. Grub hoes are best used on herbaceous annual weeds with a single central root and small- to medium-sized annual grasses. They can also be used effectively on perennials that have limited resprouting ability or that can be severed below the root crown from which they resprout. This tool does not work well on large woody plants, but it can be used to chop through small woody plants and seedlings.
Grub hoes are most useful for low-density weed infestations or for early detection and rapid response (EDRR) situations. A land manager can work small- to medium-sized weed patches before tiring. Generally, only small areas, such as several thousand square feet, can be managed with a hoe in a reasonable time with one or a few people. Hoes should be used where some soil disturbance can be tolerated.
This technique is used by land managers and volunteer groups in a wide variety of habitats. Hoes are lightweight enough to be easily carried long distances to a worksite. Many varieties of hoe types exist and a specialized hoe blade can be used for a specific job or habitat. Grub hoes are relatively inexpensive. Maintenance and upkeep are mostly limited to keeping the hoe blade sharp and ensuring the blade is secured to the shaft.
How to Use
The wide variety of blade types can alter the specific use and effectiveness of a hoe. This section will not cover all the dozens of different blade types. Note that most garden hoes available in residential garden and home improvement stores (also known as “draw hoes”) are primarily designed for creating furrows in soft soil for planting seeds and are not sturdy enough for fieldwork. The grub hoe tends to be heavier and much more robust than a draw hoe and can be used in difficult weeding situations.
The grub hoe (alternatively called chopping, digging, ring, eye, field or peasant hoe) has a ring (or ‘eye’) or collar at the top of the blade where the shaft is directly connected to the blade. The shaft of the grub hoe sits above or on the blade, which is different from a draw hoe which has a curved connector between blade and shaft. The blade of a grub hoe tends to be much thicker and heavier than a draw hoe, and some grub hoes have a slight but distinctly curved blade. The blade should be kept sharp to better chop weeds, and a small pocket file can help keep the tool sharp in the field. A sturdy grub hoe will weigh 2-5 pounds to better penetrate the roots and soil.
The grub hoe is used to cut into the soil to chop a weed below ground level and, when pulling or lifting the shaft, to turn over the soil around the roots. The shaft of the grub hoe is lifted and swung into the ground, so the blade penetrates the soil and severs weed roots or stems. The next movement is to either pull the shaft inwards towards the body to dislodge roots and soil, or to lift the shaft vertically, to minimize soil disturbance. A grub hoe can also be used to scrape the soil surface to remove weed seedlings or sever stems. Because the hoe disturbs the soil, weed seeds near the surface may become buried after using the hoe which may contribute to soil seed bank. Though a hoe can be used to clear dense weed patches, it can also be used to carefully work around non-target species.
Often a grub hoe is best used to treat weeds with a single taproot as found in many dicots, such as goat’s head (Tribulus terrestris), tumbleweed (Salsolaspp.), smaller cheeseweed plants (Malva parviflora), and dandelion (Taraxacum officinale). It can also be used to treat invasive annual grasses such as bromes (Bromusspp.) and oats (Avena spp.). If a grub hoe has a rectangular head, the user can rotate the tool 30-45 degrees to use the pointed corner to cut larger tap roots, such as on larger cheeseweed plants. In addition, when held at an angle the corner can penetrate wet soils effectively, although this will wear out the corners and they will need to be sharpened sooner.
A grub hoe with a pointed, triangle-shaped blade is also useful in situations where more delicate and precise weeding is needed compared to a rectangular grub hoe. Sometimes this hoe is called a triangle hoe or pointed hoe. (Others use the name triangle hoe for a similar tool that has a triangle shaped blade but has a wrought iron neck more similar to a draw hoe and like a draw hoe may not be sturdy enough for most wildland uses.) The blade of a triangle-shaped grub hoe is, as the name suggests, shaped like a triangle and swung like a standard grub hoe. The pointed tip is used to precisely weed around non-target plants, such as if annual weeds were growing near a native shrub seedling. The triangle grub hoe can also more easily penetrate a thick tap root, or soils that are soggy soils or compacted, than can a rectangular grub hoe. The shaft of a triangle grub hoe can be mounted to either the back of the blade forming a long triangle, which will penetrate the soil more deeply, or can be mounted in the middle of the triangle creating a tool with two working edges, one being the pointed tip and the other side being the back flat edge.
A grub hoe can also be used to treat plants with aboveground prostrate runners, such as ice plant (Carpobrotus spp.) or St. Augustine grass (Stenotaphrum secundatum). In this case the runners will need to be ‘grubbed out’ to chop large plants into smaller manageable patches. The user will need to ensure all of the plant parts are removed since small plant fragments can resprout and survive the hoeing treatment.
The hoe is easy to use on a variety of plant growth forms and habitat types. A hoe can be used any time of the year, as long as the soil can be worked. Hoeing may be most effective when flowers have developed but seeds have not yet matured on the plant. Treatments with a grub hoe will be more effective when weeds are smaller and their roots are less developed. It will also require less energy to chop out a younger plant compared to an older plant. Weeds can be treated at nearly any time in development with a hoe. Perennials can be treated at any time but should be treated before or at the flowering stage to minimize seed set.
Under dry conditions or compact soils, more force needs to be applied to swing the blade deep into the hard, dry ground. In hard soils, a grub hoe with a narrow blade will penetrate the soil better than a wide blade, and a heavy-duty triangle hoe will be even more effective, but will dull more quickly.
A high-quality grub hoe costs less than $100. With proper care and sharpening a hoe can be used for many years. The cost of the tool is cheap compared to the labor to use it, so a grub hoe is best used in treating small infestations or small areas. A person can only hoe a small fraction of a gross acre with moderate weed cover in a day. In agricultural settings, 10-25 people can hoe about 2.5 acres a day depending on the crop being grown. Density of weed cover, topography, and rockiness of soil will affect the speed of treatment. If weed cover is low, e.g. 1-5%, then a single person could manage a gross acre in a day, effectively hoeing only a few thousand square feet of weeds. The light weight of a hoe, compared to herbicides or mechanized tools, makes it a very useful tool in low-density weed infestations and in EDRR situations for non-resprouting annual weed species, where workers might hike long distances to a site. Similar benefits exist in terrain that is difficult to walk through, such as on slopes or unstable soils, where carrying a lightweight tool is safer and more efficient.
Non-Chemical Weed Control: Grub Hoes, Chris McDonald from Cal-IPC on Vimeo.
For better penetration in hard soils, use longer, skinnier hoe blades. A freshly sharpened blade will increase soil penetration and reduce user fatigue, so keep blades sharp by filing. Blades become dull more quickly when used in rocky or cobbly soils.
Under conditions where the soil is hard, a grub hoe can be used to sever weeds at ground level by scraping, although oscillating hoes are generally preferred for this (see Scuffle Hoeing BMP). In soils that are moist, loamy or soft, a grub hoe may be used to pull out weeds by pulling the hoe across the soil surface.
Consider which of the many grub hoe designs may be most useful for your situation. . Forked hoes are used more for dislodging weed roots in loose soils (see Cultivation BMP). Some hoes are designed for niche uses such as planting tree seedlings (i.e. a hoedad). A variety of hybrid tools are also available that combine a hoe blade with other tool heads. For instance, a mattock combines a pick and a hoe implement in its dual-purpose head.
Optimal Conditions for Use
The grub hoe is most effectively used for plants that crown sprout, are shallowly rooted, or are not too woody, in soils without rocks or cobbles, and in relatively flat terrain.
In order for control with a hoe to be successful, all parts of the weed that can produce new plants must be severed from their roots. If the plant can resprout or form underground storage structures, such as nutlets, bulbs, or corms, hoeing plants may not be sufficient to control the population. If hoeing does not completely remove plants that can regrow from plant fragments, the technique may actually help to propagate rather than suppress a weed. Hoeing can disturb soils, creating areas where some weed species may thrive (including tumbleweed Salsola spp., mustards Brassicaspp., and stinkwort Dittrichia graveolens). Soil disturbance may also bury weed seeds promoting future germination through a seed bank.
Potential Hazards to Humans, Environment, and Cultural Resources
Human hazards. Low. The most direct hazard from using a hoe is being struck with the blade or shaft. Workers should be well separated so they do not injure one another when swinging a hoe or striking the blade on the ground. Worker training is advised. A good rule of thumb is 10’ spacing between workers (“watch your dime!”). Closed-toe shoes or boots may prevent or lessen injury if struck on the foot with a hoe. If used too aggressively users may get blisters on their hands or may get fatigued quickly. Workers should use a hoe that allows them to stand upright without too much bending to lessen the strain on the back. Finding the right type of hoe blade, shaft length, balance of the hoe, and regular sharpening may alleviate these problems and improve ergonomics. Repeated stooping can cause significant back injury especially with too short a handle or if the hoe is used improperly or not sized properly for the worker. The short-handled hoe has been banned from use in the professional contractor industry in California for worker-safety reasons.
Cultural resources. Moderate. A hoe can damage objects below ground so it should be used with caution in culturally sensitive areas.
Habitat. Moderate. Hoeing can disturb soil, creating conditions where some weeds thrive, especially in high light environments. This tool can also disturb biological soil crusts in a wildland setting.
Sensitive species. Low-moderate. Hoeing may damage small animal burrows.
Erosion. Low-moderate. Since a hoe is relatively small and is manually powered erosion would become a risk if a large group of people were intensively hoeing a single area, especially if the site was sloped, near a streambank that could erode, or on highly erodible soils.
Consider Combining with the Following Non-Chemical Methods
Other hand tools that can remove woody weeds, such as weed pullers, saws and cutting tools (see BMP’s for those techniques) are useful when working on sites that have a variety of weed types such as annuals and woody or mature perennial weeds. On sites where precision work needs to be conducted, hand pulling or small hand tools may be needed around sensitive plants.
Don’t Use This Technique When/For
If a weed is able to reproduce vegetatively, there is a significant chance the grub hoe will not be an effective tool and may even spread plant fragments around. This includes deeply rooted perennials like perennial pepperweed (Lepidium latifolium) and Japanese knotweed (Fallopia japonica). This also includes weeds that have underground storage structures, (rhizomes, nutlets, bulbs or tubers) such as nutsedges (Cyperus spp.) and Johnsongrass (Sorghum halepense). And it includes weeds that form stolons or resprout from nodes, such as Bermuda grass (Cynodon dactylon) or Cape ivy (Delairea odorata), since the chopping action of the hoe can sever runners and numerous plant fragments may re-root in the soil.
Small patches of weeds can be easily and effectively controlled with a grub hoe with few regards to the density of the weed population. It becomes more difficult to hoe large areas and often as weed cover increases it becomes somewhat more difficult to treat every single weed in the population. Often two or more hoeing treatments are needed to catch those weeds that survived the first treatment because they may have been accidentally buried or missed.
A grub hoe can be very effective on small- to medium-sized grasses, but large perennial bunch grasses may not be an appropriate target. As shrub size and woodiness of the stem and roots increase the tool becomes ineffective. Many weedy vines are able to re-sprout from a treatment, including from plant fragments in moist soils, in those cases a grub hoe would be ineffective. Seedlings of all plant growth forms including shrubs, trees and vines can be easily treated with a grub hoe.
As long as the plant being targeted with the hoe does not re-sprout, hoeing will be effective. Many perennials can resprout when cut, even a few inches below the soil surface and hoeing treatments will not be effective. Hoeing can be a successful technique on smaller woody perennials, but it is not applicable when the stem is too woody to cut and a cutting tool would be needed (such as an ax, saw, or loppers).
When used correctly and on susceptible weeds, the grub hoe is a highly effective tool regardless of propagule production. Because the blade is relatively small nearly every plant will need to be treated to stop reproduction, thus with plants that have a high propagule production if a few plants are missed numerous seedlings may germinate next season reducing the time it will take to eliminate the population. A grub hoe could exacerbate infestations of species that readily root from plant fragments (e.g., Cape ivy) and should not be used.
Hoeing will kill the above ground parts of a plant regardless of a species’ seed longevity. This tool also disturbs the soil which may cause some seeds to be buried, benefitting those weeds with moderate and long-lived seeds, perhaps germinating after treatments have ended years later. If treatments are repeated each year and plants do not produce new seed, then this method can be used to control weeds with moderate to long-lived seeds. If plants are difficult to detect, then this method will not work well on plants with long-lived seeds as treatments may not reduce the number of seeds being produced each year.
This technique is best suited to small scale infestations and is not suited for managing medium and large-scale infestations. As scale becomes larger, it is difficult to hoe that area unless labor is increased to levels appropriate to the infestation. Hoeing large areas is sometimes conducted by large groups of volunteers or workers as the tool is relatively easy to use, requires only moderate training and can be used for several hours by healthy volunteers.
When using a hoe on loose or difficult terrain it can become difficult to properly swing a grub hoe without losing balance or risking injury. On the other hand, a long-handled grub hoe can reach weeds that are up or down a short incline where other shorter tools could not reach.
A hoe is somewhat less effective in habitats where water is present due to the fact that severed weeds may be able to re-root and continue growing. This can be mitigated by moving the cut weeds out of wet areas to places where they can dry out and desiccate. While a grub hoe can easily penetrate muddy soils, often muddy habitats can have weed species that resprout from below ground, in that case this tool would be ineffective.
DiTomaso J.M. et al. 2013. Weed Control in Natural Areas in the Western United States. UC Weed Research and Information Center: Davis, CA. 544 pp.
Holloran, P., A. Mackenzie, S. Farrell and D. Johnson. 2004. The Weed Workers Handbook a Guide to Techniques for Removing Bay Area Weeds. The Watershed Project, California Invasive Plant Council: Richmond, CA. 120 pp.
Mazoyer, M. and L. Roudart. 2006. A History of World Agriculture from the Neolithic Age to the Current Crisis. Monthly Review Press: New York, NY. 528 pp.
Winter S.R. and Wiese, A.F. 1982. Economical Control of Weeds in Sugarbeets (Beta vulgaris). Weed Science 30:620-623
Authors and Credit
Lead Author: Christopher McDonald, University of California Extension Weed Specialist, UC ANR
Phillip Cramer, Revegetation Specialist, Caltrans
Henry DiRocco, Integrated Vegetation Management Specialist, Laguna Canyon Foundation
Aaron Echols, Field Ecologist, Inland Empire Resource Conservation District
|Winter / Spring||Excellent|
|Spring / Summer||Excellent|
|Plant||Plant Growth Form|
|Low (<1000/square meter)||Excellent|
|Moderate (1000–10,000/square meter)||Good|
|High (>10,000/square meter)||Poor|
|Plant||Rate of Spread|
|High (doubling in <10 year)||Good|
|Moderate (50–75% increase in 10 years)||Excellent|
|Slow Rate (25% increase in 10 years)||Excellent|
|Plant||Resprouting / Regenerative Capacity|
|Short (≤3 years)||Excellent|
|Moderate (4–10 years)||Good|
|Long (>10 years)||Good|
|Plant||Type of Reproduction|
|Seed & Vegetative||Good|
|Plant||Type of Vegetative Reproduction|
|Rhizome / Stolon / Stem||Ineffective|
|Bulb / Corm / Tuber||Poor|
|Root sprout / Sucker / Crown sprout||Poor|
|Site||Existing Desirable Plant Cover|
|Marsh / Wetland||Good|
|Woodland / Forest||Excellent|
|Site||Level of Tolerable Disturbance|
|<40 square feet||Excellent|
|Site||Targeted Invasive Plant Cover|
|<100 feet from road||Excellent|
|100–1000 feet from road||Excellent|
|>1000 feet from road||Good|