Arsenal herbicide is a more cost-efficient tree and brush killer than Roundup because it kills trees at lower concentrations than Roundup. However, Arsenal application also brings greater risk. Arsenal attacks all types of plants and grasses and remains active in the soil, preventing future regrowth for 1–5 months.
In comparison, Roundup is less effective at clearing tough brush. Multiple applications may be required to kill trees, making it less cost-effective than Arsenal. However, Roundup has the benefit of being inert in soil. You can replant an area treated with Roundup 3 days after application.
Table of Contents
What is Arsenal Herbicide?
Arsenal is the brand name for the herbicide Imazapyr. This herbicide solution attacks plants through the leaves, roots, or cuts in the bark and disrupts amino acid synthesis, resulting in the death of the affected plant.
- Arsenal is a product that contains the herbicide Imazapyr.
- It is a non-selective herbicide that attacks all actively growing plants, trees, and grasses.
- Arsenal is absorbed through leaves, roots, and cuts in bark.
- Arsenal remains active in the soil for 1–5 months.
Arsenal controls a wide range of plants, and can kill trees, weeds, woody plants, and all types of grass. Keep in mind, a lawn sprayed with Arsenal will die, so use it carefully around desirable species of plants.
What is Roundup?
Roundup is the brand name for a line of products that typically include the active ingredient Glyphosate. Glyphosate is a post-emergent, non-selective herbicide that attacks all actively growing plants, from grass, to weeds, to trees and shrubs.
- Roundup products typically contain Glyphosate as the active ingredient.
- Glyphosate is a non-selective herbicide that attacks all plant species.
- Glyphosate (Roundup) is only absorbed through the leaves and cuts in bark.
- Roundup is inert in soil. After Roundup treatment, an area can safely be replanted in 3 days.
Roundup is remarkable for its ability to only attack target plants. It does not remain dangerous once it reaches the soil and will not attack plants through the roots. Also, because it bonds with soil particles, it is unlikely to wash into nearby water sources.
Comparison: Arsenal or Roundup?
Which should you choose: Arsenal or Roundup? We’ll walk through the best uses of both these products so you can get the job done as efficiently and cheaply as possible. For the purposes of this article, we will be comparing the following two products:
- Alligaire Imazapyr: with 52.6% Imazapyr, the active ingredient in Arsenal.
- Roundup Super Concentrate: with 50.2% Glyphosate.
These products compare well because they have similar high concentrations of their active ingredient. This allows us to see which product really gives you the most value for your dollar.
What Does Arsenal Herbicide Kill Compared to Roundup?
Both Arsenal and Roundup are non-selective weed killers. This means they kill every type of plant, whether it’s turf grass, trees, dandelions, woody plants, or vegetables.
- Both Arsenal and Roundup are non-selective herbicides.
- Arsenal and Roundup both kill over 100 species of plants, from maple trees to Kentucky Bluegrass.
- Arsenal is more powerful at lower concentrations than Roundup, making it better for bigger woody plants like trees and brush.
Arsenal is a seriously strong herbicide. While Roundup can wipe out weeds and grass no problem, Arsenal does all that and more. It’s the superior choice for attacking trees, brambles, vines, and brush.
What is the Best Use for Arsenal?
Arsenal is typically used as a tree-killing herbicide, either as a stump treatment or to kill standing trees and brush. It can attack brush through a foliar spray (application to leaves) but is most effective at killing trees through the use of the hack and squirt method or poured into holes drilled in the trunk.
- Killing trees through cuts/holes in the bark.
- Attacking brush and vines through a foliar spray, or when applied to cut stems.
- Clear brushy areas or thin out unwanted trees with Arsenal.
Arsenal is the most effective and cost-efficient when used to attack tough brush and trees. When used in this application, it outshines Roundup.
What is the Best Use for Roundup?
Roundup is ideal for killing weeds, sedge, and unwanted grass down to the root. It has the added bonus of not being active in the soil, so it is a great solution for killing plants in an area where you plan to build a new garden or install a lawn.
- Killing weeds and grass growing in undesirable areas.
- Clearing grassy/weedy area before installing a new lawn or garden.
- Can be used to kill trees and brush, but requires high concentration and multiple applications to do so.
Roundup spray diluted to 2% Glyphosate is an efficient, effective way to wipe out weeds and grasses. It controls common weeds with a single application at very low toxicity rates.
What is the Best Herbicide to Kill a Tree: Arsenal or Roundup?
When you need to kill a tree, use Arsenal. Imazapyr (Arsenal) diluted to 6–9% is more effective at killing trees than Roundup at 50% Glyphosate concentration. This means that 10 ounces of this Imazapyr product in 1 gallon of water is as effective as an entire gallon of undiluted Roundup Super Concentrate. Not only that, but even when diluted Arsenal is better at killing trees permanently, according to this study by Penn State University.
- Arsenal is more effective at killing trees than Roundup.
- Arsenal diluted to 6–9% concentration kills trees more effectively than Roundup at 50% Glyphosate concentration.
- Because Arsenal kills trees at lower herbicide concentrations than Roundup, it’s far more cost-efficient to use Arsenal to kill trees than Roundup.
A single quart of Arsenal has more tree-killing power than 3 gallons of Roundup Super Concentrate. You’ll get far better results using Arsenal to kill trees, at approximately 1/6 of the cost.
Will Arsenal Herbicide Kill Pine Trees?
Pine trees have a natural resistance to Arsenal and other tree-killers, including Glyphosate and Tordon. Killing a mature pine tree may require patience and several applications. To kill a pine tree with Arsenal, do the following:
- Cut gashes into the pine tree at a downward angle. Gashes should be deep enough to penetrate the bark and expose the light sapwood beneath (about 1/4–1/2 inch). Gashes should be 2 inches wide and should be made every 2 inches in a belt around the tree.
- Instead of gashes, you can drill holes into the pine tree. Use a 1/2 inch drill bit to drill 1–2 inch deep holes. Angle the holes downward at 45 degrees. Drill a hole every 2 inches around the circumference of the tree.
- Fill the gashes/holes with Arsenal within 10 minutes of making them.
- Allow 1–2 weeks to see tree damage and death.
This process will yield the best results. It is best performed in summer or fall to cause the pine to pull the herbicide down into the roots. By using this method you can effectively kill a pine tree.
Should You Use Arsenal or Roundup?
If you need to kill trees, use Arsenal instead of Roundup. Arsenal has much higher effectiveness in killing trees permanently than Roundup. However, for control of grass and weeds, use Roundup as your herbicide solution. Roundup is non-toxic to the soil, making it great for clearing areas prior to replanting. Arsenal, on the other hand, is active in the soil for 5 months after application, so it should be used with care, mostly in tree-killing applications.