Rodents without poison, step by step
Interactive lesson: protecting grain from mice and rats — who gets in, the signs, sealing gaps, a tidy yard, cat and owl, traps and safe cleaning.
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The whole lesson as text
1. Who gets into the store
The animals that get into grain stores are mostly mice and rats.
- House mouse — Body 7–10 cm (3–4 in), tail as long as the body, grey-brown. It moves 3–10 m from the nest and doesn't need water.
- Brown rat — Body 20–25 cm (8–10 in), heavy, blunt snout, shorter tail. Wary of anything new, moves 30–50 m and needs water every day.
- Black rat from above — Slimmer, pointed snout, tail longer than the body. An excellent climber: it comes in through the loft and the roof.
- The damage is fouling — A mouse eats roughly 3–4 g a day, but leaves 50 or more droppings. Fouled grain is not eaten and not fed to livestock.
Why: They differ in size, behaviour and how you keep them out. A pair of mice that gets into the larder in October can be a family of several dozen by spring.
- A female mouse has 5–10 litters a year, and the young are mature in 6–8 weeks. Acting early is ten times easier than acting late.
- The edible dormouse (in parts of southern England) and squirrels fall under special rules. Check with Natural England or your state wildlife agency before you trap them.
2. Signs that they're there
Rodents are nocturnal, and by the time you see them there are already many.
- Droppings — Mouse: 3–6 mm, like a grain of rice, pointed. Rat: 12–20 mm, like a bean or a capsule.
- Gnawing — A mouse leaves fine shavings and small holes in sacks. A rat makes holes of 5–8 cm (2–3 in) and gnaws bin rims, wood and cables.
- Runs along the wall — A mouse leaves fine tracks in the dust along the wall. A rat beats a path and leaves dark greasy smears along the wall and round the edges of holes.
- Powder test — In the evening, dust a thin layer of flour or talc along the wall or in front of a hole. In the morning you see footprints, tail marks and the direction they travel.
Why: So look for signs: droppings, gnawing, runs and smell. The signs tell you whether it's mice or rats and where they come from.
- A sharp smell of urine (ammonia) means mice; a strong, stale smell means rats.
- Scratching in the wall and ceiling at night is a mouse. Heavier movement and squeaking is a rat.
3. Shut them out · Locked
When you buy the module Rodent control without poison, you get a PDF to download and print and lasting access to this interactive lesson: all 6 chapters, 25 steps.
4. Yard, cat and owl · Locked
When you buy the module Rodent control without poison, you get a PDF to download and print and lasting access to this interactive lesson: all 6 chapters, 25 steps.
5. Traps · Locked
When you buy the module Rodent control without poison, you get a PDF to download and print and lasting access to this interactive lesson: all 6 chapters, 25 steps.
6. Cleaning up after rodents · Locked
When you buy the module Rodent control without poison, you get a PDF to download and print and lasting access to this interactive lesson: all 6 chapters, 25 steps.