Today, a chicken roast is a popular and inexpensive meal, and simple too, just a matter of popping to the shop and buying a prepared bird for the oven.
But it was not always like that. Traditionally birds used to be hung on display by the feet outside poultry dealers, and preparing them for eating could be a palaver.
"There was not much poultry eaten," says Mr Walls, who lives in Codsall and will turn 92 in September.
"It was because there was limited shelf life. Therefore the butcher or game dealer found it difficult to stock because he had to sell it fairly quickly."
We have published the photo showing Mr Walls and Charlie Wood in that hut before, but Mr Walls says we have never explained its significance.
"The picture would have been taken in late 1956 or early 1957 in an ex-Army shed or building that had been left on The Grove premises at Craven Arms after the Army had been there during the war.
"The significance is that it was the beginning of the changeover from growing cockerels for table birds, to growing a genetically selected bird which would give you a 4lb bird in something like seven or eight weeks. It was quite a historic period in the poultry industry."
Mr Walls had been a student at Harper Adams Agricultural College, near Newport, for three years, before going to The Grove in 1956, living-in and carrying his new bride Mima over the threshold.
"I lived at The Grove – I don't know whether it was the Dower House or chauffeur's house. It was a large Victorian house."
The poultry company of J P Wood and Sons, headed by Charlie Wood, had just moved from Market Street in Craven Arms to The Grove on the outskirts of the town, and Mr Walls went there as the poultry specialist.
"At the time J P Wood's main business was game and rabbits, fruit and vegetables. The poultry was mainly limited to old hens that had finished laying."
The move however was the start of the building of a huge poultry empire.
Mr Walls arrived armed with ideas gained from Dr Harold Temperton, vice principal at Harper Adams.
"He was an avant-garde poultry man, a geneticist by profession, who was up-to-date on American systems for growing table chickens, which were called broilers.
"In the 1950s poultry was sold hanging by its legs having been bled and feathered, but not eviscerated, because once you eviscerate a bird you contaminate the carcase and the shelf life is significantly reduced.
"So what we were talking about when the photograph was taken was that if you got the right bird, fed a suitably formulated ration, and provided with the right environment, you could mass produce broilers in this country.
"The problem we had was that the poultry breeders were not producing table birds but were breeders of world-class laying birds. The table birds were the by-product of that, the cockerel, which was very unsuited for growing on for meat.
"In the picture are cockerels bought from Hereford Hatchery. The cockerels were totally unsuited as table birds, the meat to bone ratio was poor with uneconomical food conversion.
"We did our best to secure the right type of bird – that was the whole secret. I could formulate a suitable ration, create the right environment and provide the right buildings, but we had not got the bird. They had to come from America."
A company called Sykes from Wiltshire had managed to secure some broiler breeding stock from America, so Wood's dealt with them.
"What we did then was quite straightforward, building some very large broiler houses at The Grove, and bought the appropriate ration for them from a specialist animal feed producer up in Lincolnshire. I provided the management on the farm.
"We had one of the first large broiler growing units in Shropshire. And while this was going on J P Wood was developing the processing plant at The Grove to process them."
Having got things right, expansion was explosive, and in five years the output of chickens, by now sold under the brand name “Chukie”, and turkeys, had increased twentyfold.
"I went to Africa in October 1959 to join an American poultry breeding company and by that time it had gone from having virtually nothing there to a large broiler, turkey and poultry processing unit. We encouraged a lot of local farmers to produce broilers and they would send those to the processing plant at The Grove."
The firm became a major Shropshire employer and its brand a household name, but sadly in 1990 the closure of the plant was announced with the loss of over 500 jobs.