A machine that performs beautifully on a dry loam at four kilometres an hour is a different machine on wet clay at seven. Farmers know this, which is why performance claims made without conditions are treated as marketing rather than data. The engineer who tested the machine knows it too. Somewhere between the test cell and the brochure, the conditions fall out — and with them, the only thing that made the number meaningful.

We edit what agricultural engineers and machinery specialists produce — machine test reports and performance data, technical specifications and capacity ratings, operator manuals and safety instructions, maintenance and service documentation, field trial protocols and results, irrigation and drainage system design reports, livestock housing and ventilation design documentation, grain storage and drying system specifications, precision agriculture and guidance system documentation, machinery safety assessments and guarding documentation, environmental permit and slurry management documentation, and dealer and technician training material. Our editors work on the document a buyer or an operator relies on.

The test report is where agricultural engineering earns or loses trust, and the discipline is simply that every number carries the conditions that produced it. A stated capacity of eighteen tonnes an hour is not a property of the machine; it is a property of the machine, the crop, the moisture, the ground and the operator on the day. We write these so each result is reported with the soil type and condition, moisture content, crop variety and yield, slope, forward speed and settings, because a reader in different conditions can then estimate rather than guess; so the number of replications and the variation between them is given, since a single pass is an anecdote and three passes with a range is data; so the test's departures from any standard method are declared rather than glossed, given that partial adherence described as conformance is what destroys a report's standing; so the conditions under which performance falls away are reported alongside the headline, as a manufacturer who publishes the limit is trusted on the maximum; and so the operator's contribution is acknowledged where a skilled operator was used. Reports written this way get quoted by advisers, which is worth more than any brochure.

Everything you send is treated in confidence, including trial data, designs and commercial information. We are editors rather than agricultural engineers or agronomists, and we offer no view on machinery, test methods or results. What we can do is keep the conditions attached to the numbers.