Hedge Trimmer vs String Trimmer: Which Tool Cuts What on Your Property

In the hedge trimmer vs string trimmer choice, the plant decides: blades cut leafy shrub stems, and a spinning nylon line cuts grass and light weeds at ground level. Makers do not rate a string trimmer for hedges, and a hedge trimmer is not built for grass.

I keep a hedgerow beside mown strips on a 3.7-acre orchard, so both tools get used on the same edge, and the biggest difference I see is what each one throws or cuts when something goes wrong. Below I compare the cut, the safety, the attachments and the right tool per job.

Hedge Trimmer vs String Trimmer: What Each Tool Cuts

A hedge trimmer moves two toothed blade bars against each other and shears leafy and young shrub stems up to the size its maker states. A string trimmer spins a nylon line, and the tip of that line does the cutting on grass and light weeds at or near ground level. Store signs and neighbors call the string trimmer a weed wacker, which makes hedge trimmer vs weed wacker the same comparison in other words. My guide on how a hedge trimmer works explains the motor, the gears and the blades behind that shearing action.

Put string trimmer vs hedge trimmer on one page and the cutting part explains almost everything: shearing blades for stems, a whipping line for grass. The rest of this guide covers how each tool cuts, what each should never be forced through, and how the risks differ.

How the Two Tools Cut

The cutting part decides what a tool can do, so it is worth a minute to see how each one works before comparing the jobs. One cuts with a shearing pair of blades, the other with the tip of a line moving fast. My guide on how a string trimmer works walks through the head, the line and the drive.

Blades and Cutting Capacity

A hedge trimmer drives two toothed bars that slide against each other, so a stem between the teeth is sheared. The maker’s cutting capacity says how thick a stem the blade can take, and makers measure it in different ways. Echo prints a maximum diameter cut of 1 inch for soft material but only 1/2 inch for woody material on its HC-2020 gas model. Ryobi prints a cutting capacity of 1 inch on its RY40602 and says never to cut any material with a diameter larger than that. Makita says not to attempt branches thicker than 10 mm in diameter on its XHU02, and Milwaukee prints a cutting capacity (blade gap) of 1-1/4 inches for its 3033-20.

The numbers are not interchangeable, because one is a stem, one is a branch and one is the space between the teeth. Read the exact wording in your manual, and treat anything thicker as a job for loppers or a pruning saw. I compare the jobs suited to powered blades and hand pruners in my hedge trimmer vs pruning shears guide.

Spinning Line and the Tip Rule

A string trimmer spins a head at the bottom of a shaft, and nylon line sticks out on both sides. The line has no edge, and it cuts grass because the tip is moving fast. EGO says to allow the very tip of the line to do the cutting, and Husqvarna says it is the end of the cord that does the work. Keep the line parallel to the ground and let it work at its own pace.

Line size is set by the maker for the motor, which is why my guide on what trimmer line to use starts from the manual: EGO specifies 0.095 inch line for its ST1610T, and Craftsman allows only 0.065 inch round line on its CMCST900. Metal line, wire and rope are never allowed, because they can break off and become projectiles.

Why a String Trimmer Is the Wrong Tool for a Hedge

A string trimmer cannot do hedge work, and its makers say so. Greenworks states in its string trimmer manual that you cannot use the machine to cut or chop hedges, shrubs, bushes, flowers and compost. The manual describes the job as grass, light weeds and similar vegetation at or around ground level, with the cutting plane roughly parallel to the ground.

A hedge asks for the opposite motion. The line would be held vertical or at an angle beside upright stems, so the guard no longer sits between you and the cut, and the spinning line throws leaf and wood toward your face. EGO also warns that tree bark, siding and fence posts are easily damaged by the line, and Husqvarna says the cord can damage the sensitive bark of trees and bushes.

The line also cuts whatever it touches. Milwaukee warns that rotating line will cut and damage many materials. On my orchard edge the drip line runs near the base of the hedgerow, and that is the reason I keep the head away from the shrubs and the tubing.

What a Hedge Trimmer Should Not Cut

A hedge trimmer is built for leafy shrub stems within a stated size, and the limits matter as much as the strengths. Two jobs are tempting and wrong: stems that are too thick, and grass or ground-level cleanup. In my guide to what a hedge trimmer is, I explain its types, parts and limits.

Stems Above the Maker’s Capacity

Picture a privet hedge whose new soft shoots measure about 1/2 inch, with a few old woody stems of 1 inch. The Echo HC-2020 takes soft material up to 1 inch but woody material only up to 1/2 inch, so the old woody stems are beyond what it is built to cut. The Ryobi RY40602 allows material up to 1 inch in diameter, which leaves a 1 inch stem at the limit with no margin, so I treat it as too thick. The old woody stems go to loppers or a pruning saw, and the soft shoots stay with the trimmer. My hedge trimmers for thick branches list explains the cutting capacity of seven picks.

Ryobi, EGO and Milwaukee all say not to force the blade, and Milwaukee warns that a trimmer that slows down may stall or kick. If the blade slows or the motor strains, stop and switch to a hand tool. Do not make the cut with the trimmer you already hold.

Grass and Ground-Level Work

Makers describe hedge, shrub and stem work for their hedge trimmers, and I do not recommend them on grass. A hedge trimmer working near the ground meets stones, stakes and wire. Ryobi says never to use a blade again after it hits a hard object without inspecting it for damage, and DeWalt and Ryobi both tell you to look through the hedge for wire and fence before the blade runs.

Tall grass is a string trimmer job, and my string trimmers for tall grass were chosen for overgrown ground. EGO says to cut grass over 8 inches from the top down in small steps, and to remove no more than 8 inches in each pass, so grass does not wrap the head.

Safety Differences Between the Two Tools

The two tools hurt people in different ways. A string trimmer sends objects at you, and a hedge trimmer cuts whatever touches the blade. Knowing which hazard you have decides what you wear and where you stand.

String Trimmer Hazards

In US emergency department data for 2000 to 2009, the head was the most commonly injured body part in lawn trimmer injuries, the eye was the leading single site, and most injuries were due to foreign objects (1). A case series of lawn trimmer eye injuries in Taiwan found an intraocular foreign body in most eyes, usually metal (2). Both cover lawn trimmers in general, so I read them as a warning about eyes and thrown objects.

The makers agree. EGO, Echo, Husqvarna, DeWalt and Craftsman require ANSI Z87.1 eye protection, and Greenworks points out that everyday glasses are not safety glasses. Bystander distance is the maker’s number: 50 feet for EGO, Bosch, Echo, Ryobi, Milwaukee and Greenworks, and 100 feet for DeWalt and Craftsman. Clear stones, glass and wire first, and never lean over the guard.

Before you clear the head, change line or free a wrapped stem, release the trigger, switch the motor or engine off and wait until the head has stopped completely. Then take the battery out of a battery trimmer, pull the plug of a corded one by the plug, or on a gas one let the engine and muffler cool and pull the spark plug wire off. Put on gloves before you touch the head or the guard blade, and check that the head and guard are fitted tightly before power goes back on. Husqvarna warns that the cutting attachment keeps turning for a moment after the throttle is released.

Hedge Trimmer Hazards

The hedge trimmer’s hazard is the blade itself. In UK home and leisure accident data for 2000 to 2002, hedge trimmers were the second most common cause of power tool hand injuries, after circular saws (3). The data are old and British, and they do not split petrol, corded and battery tools, but they fit what the manuals warn about.

For both tools the protective gear is the same, and nothing replaces it.

Hedge Attachments for a String Trimmer Power Head

Some string trimmers are a power head with a shaft that takes different attachments, and a hedge head is one of them. A hedge trimmer attachment for string trimmer power heads is a real product class. The power head holds the motor and battery, or the gas engine on a gas system, a coupler joins the shaft, and the attachment carries the cutting part. My guide to attachment capable string trimmers compares them with dedicated models.

The manuals are strict about what fits. DeWalt says its attachment capable powerhead is only to be used with DeWalt attachments, Echo says to use only Echo attachments, and EGO says not to use attachments it does not recommend. According to EGO’s UK site, its HTA2000 hedge head has a 510 mm blade (about 20 inches) and 12 cutting angles.

A hedge head on a long shaft is a hedge trimmer, so it follows the hedge trimmer rules in full, plus the extra hazards of working up high. Weight sits at arm’s length, and the head works high, though a manual may forbid cutting overhead, as the Echo DHCA-2600 manual does. For a low hedge that a handheld trimmer reaches, I skip the long shaft, because it makes the tool harder to control.

A hedge head fits only the power head its maker lists, never every power head on the shelf. Check that list before you buy, and read the capacity and the line rules in the attachment’s own manual.

When the Hedge Is Too Tall

A tall hedge is where people reach for the wrong tool. A string trimmer cannot do it, and a hedge trimmer on a ladder is a different danger. Keep both feet on the ground. My comparison of pole and standard hedge trimmers shows which suits your hedge height.

A hedge that has grown into or near a power line is a job for the utility alone.

Noise and Vibration Compared

Husqvarna prints 81 dB(A) at the operator’s ear in the manual for its 522iHD60 battery hedge trimmer and 98 dB(A) in the manual for its 143R-II gas brush cutter with a trimmer head. Those are different machines tested under different editions of the standards, so they show what the maker prints and nothing more. Hearing protection is the answer for both tools.

Two studies add detail. A laboratory test with two participants gave gloved-hand vibration of 3.5 to 5.8 m/s2 for a grass trimmer, against 1.1 to 2.0 m/s2 for a backpack blower (4). A test with 20 young operators found the highest vibration, 5.25 m/s2 RMS, on a brushcutter among a brushcutter, an electric saw and a hedge trimmer (5). Neither test compared a string trimmer with a hedge trimmer, so neither settles which of the two shakes the hands more. I take breaks on long jobs whichever tool I hold.

Which Tool Fits Which Job on Your Property

The right tool follows the job, not the brand or the shop shelf. I sort my edge work by what is growing and how thick it is, and the table below is the sorting I use.

Owning both tools is common, and it makes sense on a property with hedges and mown edges. Buying a string trimmer and hedge trimmer that list the same battery platform and pack in their manuals lets one pack serve both, because packs do not cross brands. Between tools I release the switch, switch the motor off, wait until the blade or head has stopped completely, then take the battery pack out. The hedge trimmer gets its blade cover, and I carry it by the handle with the blade pointing behind me.

The edge between hedge and grass is where people mix the tools up. A rule I use is simple: the hedge trimmer stops at the foliage, and the string trimmer starts where the stems end. Clippings go off the drip line before the string trimmer runs, so the head does not chew them or the tubing.

Putting the Two Tools to Work

Three things carry over from this comparison. Use the blade on stems within the stated capacity and a hand tool on anything thicker. Keep the line trimmer at ground level and your face behind the guard. Wear eye and hearing protection for both. My own tip is to look through the hedge before any cutter runs, because the wire and stakes that jam a blade are the same objects a line throws. That is the whole hedge trimmer vs string trimmer decision, and the manual in your hands settles the rest. My nine hedge trimmer picks cover cordless, corded and gas models.

Frequently Asked Questions

Can you use a string trimmer for hedges?

You cannot use a string trimmer for hedges, because makers rate it for grass and light weeds at ground level. Greenworks says in its manual that you cannot use the machine to cut or chop hedges, shrubs, bushes, flowers and compost. Use a hedge trimmer within its stated cutting capacity instead.

Can I use hedge trimmers to cut tall grass?

Hedge trimmers are made for leafy shrub stems, and their makers describe hedge and stem work, not grass. Near the ground a blade meets stones and wire, and Ryobi says to inspect a blade after it hits a hard object. Tall grass is a string trimmer job, cut from the top down in small steps as EGO describes.

What are the key differences between a brush cutter and a hedge trimmer?

A brush cutter turns a trimmer head or a blade at the end of a shaft to clear thick grass and woody growth, while a hedge trimmer moves two toothed blade bars to shear shrub stems. Only a machine whose manual lists a blade takes one, and Husqvarna warns that a blade can be thrown violently to the side on contact with a fixed object. Never fit a blade your manual does not list.

Can I use a hedge trimmer to cut bushes?

A hedge trimmer cuts bushes whose stems are within the maker’s stated capacity, such as a material diameter of 1 inch on the Ryobi RY40602 or branches up to 10 mm in diameter on the Makita XHU02. Echo prints a maximum diameter cut of 1 inch for soft material but only 1/2 inch for woody material on its HC-2020, and thicker stems go to loppers or a pruning saw. Look through the bush for wire and stakes before the blade runs.

Does a hedge attachment for string trimmer power heads work like a hedge trimmer?

A hedge attachment for a string trimmer power head is a hedge trimmer on a long shaft, so it follows the hedge trimmer rules, not the string trimmer rules. It fits only the power head its maker lists, and DeWalt and Echo say to use only their own attachments. Check its capacity and the power line distance in its own manual.

References

1. Leinert J, Griffin R, Blackburn J, McGwin G. The epidemiology of lawn trimmer injuries in the United States: 2000-2009. J Safety Res. 2012;43(2):137-139. doi:10.1016/j.jsr.2012.03.001
2. Zhang JR, Hsieh TC, Chang FL, He MS. Lawn trimmer-related open-globe injuries in Taiwan. Retina. 2022;42(5):973-980. doi:10.1097/IAE.0000000000003402
3. Williams STB, Power D. Hand injuries from tools in domestic and leisure settings: relative incidence and patterns of initial management. J Hand Surg Eur Vol. 2011;36(5):408-412.
4. Oh J, Chen N, Boyd C. Laboratory evaluation of occupational exposure to hand-arm vibration (HAV) during grounds maintenance equipment operations. Ann Agric Environ Med. 2023;30(2):384-389.
5. Roggio F, Vitale E, Filetti V, Rapisarda V, Musumeci G, Romano E. Ergonomic evaluation of young agricultural operators using handle equipment through electromyography and vibrations analysis between the fingers. Saf Health Work. 2022;13(4):440-447. doi:10.1016/j.shaw.2022.07.003

Safety Note: Only an adult who has read the manual and understands the controls should use a hedge trimmer, never a child or anyone tired or impaired. The blades are sharp, a hand that touches them is cut in a fraction of a second, and they keep moving for a moment after you release the switch. Hold the trimmer with both hands on the handles, by the insulated gripping surfaces only because the blades can contact hidden wiring (the grips do not make the trimmer insulated or wire contact safe), whenever the blades move; on a trimmer with two switches, both hands must be on the switches to start. Never hold a branch or reach toward the blades, through the hedge or into any opening while they move, and never reach into any opening of a gas trimmer while the engine is running, because a blade that stops in a jam does not stop the engine. Never overreach, and trim only what you can see. Before you start, look through the hedge for wire, fence wire, cords, posts, stakes, irrigation lines, nests, people and pets, and keep the cord or hose out of the blade’s path. If a blade jams on a wire or a cord, do not touch the blade, the wire or the cord: stopping the blade does not remove the electrical danger, so the electrical supply to the damaged line or cord must be disconnected first. Cut only stems up to the capacity your manual states, in the maker’s own wording, and leave thicker wood to loppers or a saw. Do not use a hedge trimmer from a ladder, a roof, a tree or any unstable support, so for a tall hedge stay on the ground and use a pole or long-reach hedge trimmer, or hire a professional. Power lines can kill. With a pole or long-reach hedge trimmer, look for every overhead wire, including wires hidden in leaves, and keep yourself, the trimmer, the pole and any branch that could fall or swing at least 50 feet (15 m) from every line, the distance Ryobi and Echo print in their pole hedge trimmer manuals, or farther if your manual asks for more. A pole hedge trimmer is not insulated, and electricity can jump through the air and travel through branches, especially wet ones. Treat every wire as live, and leave a hedge that has grown into or near a wire to the utility and its qualified line-clearance crews. If the trimmer, the pole or a branch touches a wire, treat the trimmer, the branch, the wire and anything touching them as live: do not go back to the trimmer to switch it off or unplug it, do not touch anything in contact with the line, keep everyone away and call the utility, which alone frees the trimmer, and 911 if anyone is hurt, a fire starts or a line comes down. Wear safety glasses with side shields marked Z87.1, a face shield over the glasses where your manual asks for one, hearing protection, sturdy gloves, long pants, long sleeves with no loose clothing or jewelry, and closed, non-slip shoes. Wear head protection when you work a pole or long-reach model overhead, as the Ryobi, Husqvarna and Echo pole manuals require, and a respirator when dust is present, as the DeWalt manual states; where a manual forbids cutting overhead, do not. Keep people and pets away at the distance your manual gives, and stop trimming if anyone comes closer. Never trim in rain, fog, strong wind, a storm or when lightning is possible, trim only in good light, and let the hedge dry first. Before each use, remove the blade cover (it is for carrying and storage only), and check the blades, the operating guards, the switches and every handle and pole coupling as your manual describes, and do not use a trimmer that fails a check. Before you clear a jam, remove cut material, clean, lubricate or touch the blades: release the switch, switch the motor or engine off and wait until the blades have stopped completely, then take the battery pack out, unplug a corded trimmer from the outlet by the plug, or on a gas trimmer let the engine and muffler cool and pull the spark plug wire off; put on gloves and check every lock and coupling before power goes back on. To carry or store the trimmer, release the switch, switch the motor or engine off and wait until the blades have stopped completely, then take the battery out, unplug a corded trimmer by the plug, or on a gas trimmer let the engine and muffler cool and pull the spark plug wire off; fit the blade cover, carry the trimmer by the handle with the blades pointing behind you, and keep it indoors, dry and out of children’s reach. Use only the maker’s battery and charger, charge and store them within the temperatures your manual gives and never in the wet, never use or charge a damaged, swollen or leaking pack, and keep loose batteries away from metal objects that could short the terminals. Use a corded trimmer only with an outdoor-rated extension cord of the gauge your manual gives, plugged into GFCI-protected power, with the cord behind you and away from the blades, and never in rain or wet conditions: GFCI protection does not make that safe; if the cord is cut or damaged, disconnect it at once by pulling the plug from the outlet by the plug, before you touch the cord or the blades. Refuel a gas trimmer outdoors with the engine off and cool, with no smoking, flames or sparks nearby, wipe up spills, move at least 10 feet from where you fuelled before you start it, wear hearing protection, and never run it indoors or in a garage or shed, because the exhaust contains carbon monoxide. Look for nests before you cut and leave a hedge where birds are nesting. Take breaks and stop when you are tired.