The recent difficulties of British farmers – migrant workers no longer wish to work in low-paid temporary jobs far from home, because a drop in the value of pound removes the only advantage – are not going to disappear (Food left to rot as 4,300 farm jobs went unfilled, 10 February).

But there is an answer to this supply problem: national service. All students in tertiary education could be required to register for work in seasonal agriculture. Universities should organise their term times and vacations in accordance with the needs of the nearest agricultural areas. This was the origin of the “long vacation”, when students went home to help with the harvest.

Universities may try to object because they are important international organisations etc. But they should be told that cooperation is their contribution to the common good. The students’ wages should be a reduction to their (currently exorbitant) fees and loans. However, rich students should not be allowed to opt out. Subsistence and accommodation (if necessary) would be provided. It would be nice if second-home owners of former “agricultural labourer” cottages had to give them up for a month or two a year – perhaps a suggestion too far for our unequal world.

An extra advantage would be that modern students would gain some understanding of that most fundamental of activities: food production. When I was a small country child, the autumn half term was “the potato-picking holiday”. As urban teenagers, some of us went on camping trips to pick fruits and vegetables. Even then, leek-picking in winter was strictly for the hardy and hard-up professionals.

Aileen Hammond

London

• The prospect of a post-Brexit trade deal with Donald Trump helping fuel the looming antibiotic apocalypse is a real one (Huge level of antibiotic use on US farms intensifies fears over post-Brexit trade, 8 February). But we have less time to prevent it than you might think.

The government’s trade bill, which last year’s Queen’s speech promised would set the framework for post-Brexit trade deals, is rapidly proceeding through parliament. The framework it sets is one which gives MPs no power to block or amend future trade deals – with Trump or anyone else – whether they are clearing the way for antibiotic-pumped beef, chlorinated chicken, or indeed increased private involvement in the NHS (Theresa May refuses to exclude NHS contracts from US trade deals, theguardian.com, 7 February).

Parliament is the people’s “medicine of last resort” for a government overcome by infected priorities. When the trade bill returns to the Commons in the coming weeks, MPs must amend it to make trade deals fully accountable to our elected representatives – and fully blockable if need be. This is the only way to avoid the “superbug” of trade secretary Liam Fox enjoying unchecked power over vast areas of our lives, from the food we eat to the services we rely on.

Jonathan Stevenson

Global Justice Now

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