Feed storage is a vital part of modern farming, and ag bags have become a popular, flexible, and low-cost solution suitable for every size farm. While most commonly used for silage, ag bags are also highly effective for storing maize, whole crop cereals (such as wheat and barley), miscanthus, grains, sugar beet pulp, and a wide variety of by-products.
In the UK, the storage of silage is governed by the Water Resources (Control of Pollution) (Silage, Slurry and Agricultural Fuel Oil) Regulations 2010 (SSAFO). These regulations are enforced by the Environment Agency (EA) in England and Natural Resources Wales (NRW) in Wales. While the rules are largely identical in both countries, understanding and following them is essential to protect water resources, maintain compliance, and ensure the safety and quality of stored feed.
What is an ag bag?
An ag bag is a large, airtight plastic tube designed to store silage, maize, cereals, and other feed materials in bulk. It offers farmers a versatile and cost-effective alternative to traditional clamps or permanent storage structures.
The airtight environment prevents the growth of aerobic bacteria, moulds, and insects. It eliminates the need for chemical preservatives or fumigants and enhances the benefits of cool fermentation with optimal levels of lactic acid – without damaging heat build-up. The result is highly digestible, nutritious feed that livestock prefer, leading to better herd health and higher production without costly supplements.
An ag bag also helps reduce costly shrinkage losses, preserving feed quality and profitability.
What can be stored in an ag bag?
Ag bags are ideal for storing a wide range of feeds, including:
- Grass silage
- Maize silage
- Whole crop silage (wheat, barley, etc.)
- Breweries grain and distiller’s grain
- Wet and dry grain
- Pressed sugar beet pulp
- Whole beet
- Miscanthus and other biomass crops
This flexibility makes the ag bag a truly multi-purpose storage system that supports both feed preservation and renewable energy cropping.
How ag bags work
Ag bags provide unlimited, low-cost storage capacity exactly where you need it. Bags can be placed for convenient access, allowing feed to be removed with a front-end loader or even self-fed. Feed rations can also be blended and balanced within the bags to suit herd requirements.
Farmers can either:
- Use a professional contracting service for bagging, or
- Operate their own bagging system using PTO-driven machines (available new or second-hand).
This flexibility means that ag bags are suitable for farms of all sizes – from small family farms to large-scale operations.
Key requirements for silage storage (SSAFO Regulations)
While ag bags can store many crops, legal requirements currently apply to silage storage under the SSAFO regulations:
- Notify the relevant authority
Before using a non-baled silage store, you must notify the EA (in England) or NRW (in Wales) at least 14 days in advance – using form WQE4 in England, or the online form on the Natural Resources Wales wesite.
- Choose the right site
Ag bags must be positioned at least 10 metres away from inland or coastal waters, and 50 metres from protected water supply sources.
- Manage drainage & effluent
Silage and maize may generate effluent during fermentation. Ensure bunding or secondary containment is in place to protect watercourses. (Drier crops like miscanthus or whole grain generally pose lower effluent risks.)
- Regular maintenance & monitoring
Inspect bags regularly for punctures or tears caused by machinery, wildlife, or livestock. Repair damage immediately to prevent leaks and spoilage.
Summary checklist
- Notify EA/NRW 14 days before first use of an Ag Bag silage store.
- Choose safe storage sites away from water sources.
- Manage drainage and effluent effectively.
- Inspect and maintain bags regularly.
- Keep records of inspections, repairs, and corrective actions.
Final thoughts
Ag bags are a proven, low-cost storage option for silage, maize, cereals, miscanthus, and a wide range of by-products. They help reduce feed waste, improves herd nutrition, and offer flexibility for every size farm.
By combining these benefits with responsible management and compliance with SSAFO regulations for silage, farmers across England and Wales can store feed safely, protect the environment, and increase profitability.
For more guidance, contact our Agricultural Compliance team on 01981 590514 or visit the gov.uk guidance on storing silage, slurry, and agricultural fuel oil.