---
title: "Stump Killer Mixture Ratio: Why the Carrier Fluid Determines Whether the Treatment Works at All"
canonical: "https://theyieldgrid.com/stump-killer-mixture-ratio/"
model_id: "tyg-2774"
model_version: "1.0.0"
last_reviewed: "2026-08-25T05:16:52"
reviewed_by: "Umer Hayiat"
---

# Stump Killer Mixture Ratio: Why the Carrier Fluid Determines Whether the Treatment Works at All

> Canonical calculator: [https://theyieldgrid.com/stump-killer-mixture-ratio/](https://theyieldgrid.com/stump-killer-mixture-ratio/)

## What this calculator does

Home - Free Gardening Calculators & Tools - Stump Killer Mixture Ratio: Why the Carrier Fluid Determines Whether the Treatment Works at All Herbicide concentration is only half of the equation when treating invasive woody plants. The other half, the one that most property owners get wrong, is whether the carrier fluid can actually deliver the active ingredient into living tissue. Bark is hydrophobic. It is built to shed water. A herbicide mixed in water and sprayed onto an untreated trunk will roll off the surface before a single molecule of active ingredient crosses the bark boundary, regardless of the concentration used.

## Inputs

| Input | ID | Type | Unit | Range or choices | Required |
|---|---|---|---|---|---|
| Target Invasive Species (select species) | `stumpherbcalc_species` | select |  | — Select Species — = ``; Tree of Heaven (Ailanthus) = `Tree of Heaven`; Buckthorn (Rhamnus) = `Buckthorn`; Autumn Olive (Elaeagnus) = `Autumn Olive`; Bush Honeysuckle (Lonicera) = `Honeysuckle`; Multiflora Rose = `Multiflora Rose`; Privet (Ligustrum) = `Privet`; Other Woody Invasive = `Other` | No |
| Herbicide Active Ingredient (product type) | `stumpherbcalc_ingredient` | select |  | — Select Herbicide — = ``; Triclopyr Ester 61.6% (Garlon 4 / Remedy) = `triclopyr61`; Triclopyr Amine 44.4% (Garlon 3A) = `triclopyr44`; Glyphosate 53.8% (Roundup Pro) = `glyphosate53`; Imazapyr 28.7% (Arsenal / Habitat) = `imazapyr28` | No |
| Application Method (how to apply) | `stumpherbcalc_method` | select | how to apply | — Select Method — = ``; Cut-Stump = `cutstump`; Basal Bark = `basalbark`; Foliar Spray = `foliar` | No |
| Carrier Fluid (mixing base) | `stumpherbcalc_carrier` | select |  | — Select Carrier — = ``; Basal Oil / Diesel = `oil`; Water = `water` | No |
| Total Mix Volume (fluid ounces, 1 – 2560 oz) | `stumpherbcalc_volume` | number | fluid ounces, 1 – 2560 oz | 1 to 2560 | No |

## Outputs

| Output ID | Default state |
|---|---|
| `stumpherbcalc_results` |  |

## Formula and method

Accurate mixing requires calculating the specific volume of herbicide concentrate against the total batch volume to ensure efficacy. Show the calculation steps Step 1: Identify the target concentration range The application method determines a standard concentration range for the herbicide in the final mix: Cut-Stump: 20% to 25% Basal Bark: 15% to 20% Foliar: 2% to 3% The calculator uses the midpoint of each range as the primary displayed result, and the low and high endpoints for the breakdown columns. Step 2: Calculate herbicide volume Herbicide Amount (oz) = Total Mix Volume (oz) x Concentration Rate Example: 128 oz x 0.20 = 25.6 oz of herbicide concentrate Step 3: Calculate carrier volume Carrier Amount (oz) = Total Mix Volume (oz) – Herbicide Amount (oz) Example: 128 oz – 25.6 oz = 102.4 oz of carrier Rounding rule: All results are rounded to one decimal place. No rounding occurs during intermediate steps; only the final displayed values are rounded. Unit convention: All inputs and outputs are in fluid ounces. Volume in gallons must be converted before entry (1 gallon = 128 fluid oz). Compatibility block logic: Before calculating, the tool checks two conditions. If Application Method = Basal Bark and Carrier = Water, the calculation is blocked entirely and an absorption failure explanation is shown. If Application Method = Basal Bark and Herbicide = Triclopyr Amine, the calculation is also blocked because the amine salt formulation is water-soluble and will not penetrate bark in an oil carrier. Assumptions and Limits Concentration ranges are based on standard label guidance for woody invasive species control in the landscaping and land management context. Specific products may have narrower label-stated ranges; always defer to the product label. The calculator does not account for the concentration of the active ingredient within the commercial product (for example, the label concentration of 61.6% in Garlon 4). Concentration ranges here refer to the volume-to-volume ratio of product concentrate in the final mix, not the active ingredient mass per unit volume. Surfactant volumes are not included in the calculation. Add surfactants separately at label-specified rates after determining the herbicide and carrier volumes. Indicator dye volumes are not included. Field practice typically calls for dye addition at 1 to 2 oz per gallon of mix; this does not substantially change the herbicide concentration at those volumes. Basal bark effectiveness diminishes on stems larger than approximately 6 inches in diameter; the tool does not adjust for stem diameter. The maximum supported mix volume is 2,560 oz (20 gallons). Larger batches should be calculated per gallon and scaled manually. Cut-stump application timing is critical. The 5-minute window after cutting is a field standard, not a hard biological constant; it represents the point at which the wound response begins sealing the cut surface. This tool cannot model timing compliance. Foliar efficacy depends on weather conditions (temperature, humidity, rainfall window) that this calculator does not model. Triclopyr comes in two commercial formulations with very different properties. The amine formulation (Garlon 3A) is water-soluble and designed for water-carrier applications. The ester formulation (Garlon 4 / Remedy) is oil-soluble and designed for bark penetration. Using Garlon 3A in an oil carrier does not convert it into a bark-penetrating product; the chemistry is incompatible. Fix: Confirm the label. “Ester” formulations are required for basal bark. “Amine” formulations work for foliar and cut-stump with a water carrier.

## Verified worked examples

### Example 1: Cut-Stump Treatment on Tree of Heaven

Treating the cambium layer within five minutes of cutting prevents invasive species from resprouting through aggressive root systems. Species: Tree of Heaven (Ailanthus altissima) Herbicide: Triclopyr Ester 61.6% (Garlon 4) Application Method: Cut-Stump Carrier: Water Total Mix Volume: 128 oz (1 gallon) Rate applied: 20% (low end of cut-stump range) Result: 25.6 oz of Triclopyr Ester + 102.4 oz of water Tree of Heaven is exceptionally vigorous and resprouts aggressively from cut stumps. Apply the mix to the outer ring (cambium zone) of the freshly cut stump surface within five minutes of cutting. Missing the cambium band and treating only the heartwood wastes material and allows root sprouting to continue.

### Example 2: Basal Bark Treatment on Buckthorn (Small Stem)

Species: Buckthorn (Rhamnus cathartica) Herbicide: Triclopyr Ester 61.6% (Garlon 4) Application Method: Basal Bark Carrier: Basal Oil / Diesel Total Mix Volume: 64 oz (0.5 gallon) Rate applied: 15% (low end of basal bark range) Result: 9.6 oz of Triclopyr Ester + 54.4 oz of basal oil or diesel Basal bark is the preferred method for Buckthorn when cutting is not practical or when treating large numbers of stems quickly. Treat the lower 12 to 18 inches of the trunk, wetting the bark uniformly around the circumference. Basal bark application is effective year-round, including winter when the bark is dry, which makes it useful for off-season control work.

### Example 3: Foliar Spray on Multiflora Rose

Species: Multiflora Rose (Rosa multiflora) Herbicide: Glyphosate 53.8% (Roundup Pro) Application Method: Foliar Spray Carrier: Water Total Mix Volume: 256 oz (2 gallons) Rate applied: 2% (low end of foliar range) Result: 5.1 oz of Glyphosate concentrate + 250.9 oz of water Foliar applications on Multiflora Rose work best in late summer when the plant is actively photosynthesizing and the herbicide can be translocated into the root system before dormancy. Spray to full coverage without runoff. Adding a surfactant (per label directions) improves leaf uptake on waxy or hairy foliage, but this calculator does not account for surfactant volumes; add those separately at label rates.

## Assumptions

Accurate mixing requires calculating the specific volume of herbicide concentrate against the total batch volume to ensure efficacy. Show the calculation steps Step 1: Identify the target concentration range The application method determines a standard concentration range for the herbicide in the final mix: Cut-Stump: 20% to 25% Basal Bark: 15% to 20% Foliar: 2% to 3% The calculator uses the midpoint of each range as the primary displayed result, and the low and high endpoints for the breakdown columns. Step 2: Calculate herbicide volume Herbicide Amount (oz) = Total Mix Volume (oz) x Concentration Rate Example: 128 oz x 0.20 = 25.6 oz of herbicide concentrate Step 3: Calculate carrier volume Carrier Amount (oz) = Total Mix Volume (oz) – Herbicide Amount (oz) Example: 128 oz – 25.6 oz = 102.4 oz of carrier Rounding rule: All results are rounded to one decimal place. No rounding occurs during intermediate steps; only the final displayed values are rounded. Unit convention: All inputs and outputs are in fluid ounces. Volume in gallons must be converted before entry (1 gallon = 128 fluid oz). Compatibility block logic: Before calculating, the tool checks two conditions. If Application Method = Basal Bark and Carrier = Water, the calculation is blocked entirely and an absorption failure explanation is shown. If Application Method = Basal Bark and Herbicide = Triclopyr Amine, the calculation is also blocked because the amine salt formulation is water-soluble and will not penetrate bark in an oil carrier. Assumptions and Limits Concentration ranges are based on standard label guidance for woody invasive species control in the landscaping and land management context. Specific products may have narrower label-stated ranges; always defer to the product label. The calculator does not account for the concentration of the active ingredient within the commercial product (for example, the label concentration of 61.6% in Garlon 4). Concentration ranges here refer to the volume-to-volume ratio of product concentrate in the final mix, not the active ingredient mass per unit volume. Surfactant volumes are not included in the calculation. Add surfactants separately at label-specified rates after determining the herbicide and carrier volumes. Indicator dye volumes are not included. Field practice typically calls for dye addition at 1 to 2 oz per gallon of mix; this does not substantially change the herbicide concentration at those volumes. Basal bark effectiveness diminishes on stems larger than approximately 6 inches in diameter; the tool does not adjust for stem diameter. The maximum supported mix volume is 2,560 oz (20 gallons). Larger batches should be calculated per gallon and scaled manually. Cut-stump application timing is critical. The 5-minute window after cutting is a field standard, not a hard biological constant; it represents the point at which the wound response begins sealing the cut surface. This tool cannot model timing compliance. Foliar efficacy depends on weather conditions (temperature, humidity, rainfall window) that this calculator does not model. Concentration ranges are based on standard label guidance for woody invasive species control in the landscaping and land management context. Specific products may have narrower label-stated ranges; always defer to the product label. The calculator does not account for the concentration of the active ingredient within the commercial product (for example, the label concentration of 61.6% in Garlon 4). Concentration ranges here refer to the volume-to-volume ratio of product concentrate in the final mix, not the active ingredient mass per unit volume. Surfactant volumes are not included in the calculation. Add surfactants separately at label-specified rates after determining the herbicide and carrier volumes. Indicator dye volumes are not included. Field practice typically calls for dye addition at 1 to 2 oz per gallon of mix; this does not substantially change the herbicide concentration at those volumes. Basal bark effectiveness diminishes on stems larger than approximately 6 inches in diameter; the tool does not adjust for stem diameter. The maximum supported mix volume is 2,560 oz (20 gallons). Larger batches should be calculated per gallon and scaled manually. Cut-stump application timing is critical. The 5-minute window after cutting is a field standard, not a hard biological constant; it represents the point at which the wound response begins sealing the cut surface. This tool cannot model timing compliance. Foliar efficacy depends on weather conditions (temperature, humidity, rainfall window) that this calculator does not model. Critical Warnings The Water-Bounce Bark Failure: Applying any herbicide in a water-based carrier to uncut bark will fail. Tree bark is structurally lipophilic. The suberin and lignin layers that make up outer bark are chemically similar to wax; water-soluble solutions bead and shed without penetrating to the cambium. No amount of increased concentration or repeated application fixes this failure mode. The fix is not more herbicide; it is the correct carrier (oil-based) or a different method (cut-stump). Formulation matters as much as concentration: Triclopyr Amine (Garlon 3A) is a salt formulation designed for water-based foliar and cut-stump use. Even in an oil carrier, it does not penetrate bark reliably. Basal bark work requires Triclopyr Ester (Garlon 4 or Remedy), which is an oil-soluble ester that dissolves into and moves with the oil carrier through bark tissue. Substituting the amine formulation and using an oil carrier produces a chemically incompatible mix with poor absorption. Cut-stump timing is non-negotiable: The wound response in woody plants begins within minutes of a cut. As the parenchyma cells seal the xylem, the window for herbicide absorption shrinks rapidly. Treatments applied more than 5 to 10 minutes after cutting face a progressively sealed surface. Pre-mixing and having the solution ready before the cut is standard field practice for a reason. Foliar concentration at cut-stump rates causes non-target injury: Using a 20% concentration solution (designed for cut-stump) as a foliar spray will cause contact kill of leaf tissue without translocation to the roots, and will cause significant drift risk to adjacent non-target vegetation. Always match concentration to method. Minimum Standards Basal bark treatment requires an oil-based carrier. Basal oil products designed for herbicide work are preferred over diesel; diesel can still perform but introduces additional handling concerns. Either way, water is not an acceptable substitute for this method. All herbicide application equipment used with oil-based carriers must be compatible with petroleum-based solvents. Standard pump sprayers with rubber gaskets may degrade; use sprayers rated for oil-based chemicals. Indicator dye should be added to all field mixes to enable visual tracking of treated vs. untreated stems. Blue or purple dye is standard; it fades within days without interfering with treatment efficacy. Applicators must follow federal and state pesticide regulations. Some herbicide products require a pesticide applicator license for use on certain land types. Verify regulatory requirements for your jurisdiction before treating land other than your own property. Competitor Trap: Searches for “stump killer mixture ratio” return a large number of pages that provide concentration numbers without addressing the carrier compatibility question at all. A property owner can read those pages, mix Triclopyr Ester at the correct 20% concentration in water, spray it on standing Buckthorn stems for an entire afternoon, and return the following spring to find every treated plant alive. The concentration was right. The application was wrong. The content that stops at “use X concentration” has answered the arithmetic question while leaving the actual biology question entirely unaddressed. This calculator blocks the failing combination before a batch is mixed. Understanding the biology of the plants you are targeting also matters when planning a treatment program. Knowing the approximate age and root development of a woody invasive informs whether basal bark or a cut-stump approach will be more effective for long-term control. The critical root zone calculator can help you understand the extent of root systems when working near desirable trees you need to protect from herbicide exposure.

## Limitations and safety

Concentration ranges are based on standard label guidance for woody invasive species control in the landscaping and land management context. Specific products may have narrower label-stated ranges; always defer to the product label. The calculator does not account for the concentration of the active ingredient within the commercial product (for example, the label concentration of 61.6% in Garlon 4). Concentration ranges here refer to the volume-to-volume ratio of product concentrate in the final mix, not the active ingredient mass per unit volume. Surfactant volumes are not included in the calculation. Add surfactants separately at label-specified rates after determining the herbicide and carrier volumes. Indicator dye volumes are not included. Field practice typically calls for dye addition at 1 to 2 oz per gallon of mix; this does not substantially change the herbicide concentration at those volumes. Basal bark effectiveness diminishes on stems larger than approximately 6 inches in diameter; the tool does not adjust for stem diameter. The maximum supported mix volume is 2,560 oz (20 gallons). Larger batches should be calculated per gallon and scaled manually. Cut-stump application timing is critical. The 5-minute window after cutting is a field standard, not a hard biological constant; it represents the point at which the wound response begins sealing the cut surface. This tool cannot model timing compliance. Foliar efficacy depends on weather conditions (temperature, humidity, rainfall window) that this calculator does not model. Critical Warnings The Water-Bounce Bark Failure: Applying any herbicide in a water-based carrier to uncut bark will fail. Tree bark is structurally lipophilic. The suberin and lignin layers that make up outer bark are chemically similar to wax; water-soluble solutions bead and shed without penetrating to the cambium. No amount of increased concentration or repeated application fixes this failure mode. The fix is not more herbicide; it is the correct carrier (oil-based) or a different method (cut-stump). Formulation matters as much as concentration: Triclopyr Amine (Garlon 3A) is a salt formulation designed for water-based foliar and cut-stump use. Even in an oil carrier, it does not penetrate bark reliably. Basal bark work requires Triclopyr Ester (Garlon 4 or Remedy), which is an oil-soluble ester that dissolves into and moves with the oil carrier through bark tissue. Substituting the amine formulation and using an oil carrier produces a chemically incompatible mix with poor absorption. Cut-stump timing is non-negotiable: The wound response in woody plants begins within minutes of a cut. As the parenchyma cells seal the xylem, the window for herbicide absorption shrinks rapidly. Treatments applied more than 5 to 10 minutes after cutting face a progressively sealed surface. Pre-mixing and having the solution ready before the cut is standard field practice for a reason. Foliar concentration at cut-stump rates causes non-target injury: Using a 20% concentration solution (designed for cut-stump) as a foliar spray will cause contact kill of leaf tissue without translocation to the roots, and will cause significant drift risk to adjacent non-target vegetation. Always match concentration to method. Minimum Standards Basal bark treatment requires an oil-based carrier. Basal oil products designed for herbicide work are preferred over diesel; diesel can still perform but introduces additional handling concerns. Either way, water is not an acceptable substitute for this method. All herbicide application equipment used with oil-based carriers must be compatible with petroleum-based solvents. Standard pump sprayers with rubber gaskets may degrade; use sprayers rated for oil-based chemicals. Indicator dye should be added to all field mixes to enable visual tracking of treated vs. untreated stems. Blue or purple dye is standard; it fades within days without interfering with treatment efficacy. Applicators must follow federal and state pesticide regulations. Some herbicide products require a pesticide applicator license for use on certain land types. Verify regulatory requirements for your jurisdiction before treating land other than your own property. Competitor Trap: Searches for “stump killer mixture ratio” return a large number of pages that provide concentration numbers without addressing the carrier compatibility question at all. A property owner can read those pages, mix Triclopyr Ester at the correct 20% concentration in water, spray it on standing Buckthorn stems for an entire afternoon, and return the following spring to find every treated plant alive. The concentration was right. The application was wrong. The content that stops at “use X concentration” has answered the arithmetic question while leaving the actual biology question entirely unaddressed. This calculator blocks the failing combination before a batch is mixed. Understanding the biology of the plants you are targeting also matters when planning a treatment program. Knowing the approximate age and root development of a woody invasive informs whether basal bark or a cut-stump approach will be more effective for long-term control. The critical root zone calculator can help you understand the extent of root systems when working near desirable trees you need to protect from herbicide exposure.

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## Provenance

- Model ID: `tyg-2774`
- Model version: `1.0.0`
- Reviewed by: Umer Hayiat
- Page modified: 2026-08-25T05:16:52
- Runtime SHA-256: `6ed488f9dc1d7a81cc360e73d3f5caf7cb87b931792b88ae6aa6ec57bae1108f`

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