The pic illustrates a 15cm K16 barrel/receiver on it's rohrwagen. At first glance it appears to be on a field carraige, but that's because the wagon is missing it's forward set of wheels and the tube has been allowed to slide away from the rear chain/wench lock.
The gun was previously on display at Esholt Hall, unveiled in 1922, it was buried and then dug up again from Esholt Sewage Works - a photo of it in the 1920's shows it with the forward set of wheels present. It was donated to Beamish, which for those who don't know is a fantastic open-air museum which portrays the North East in the early 19th, late 19th and early 20th centuries - notably the town area depicts 1913, with a park where this gun now sits, which has a plaque commemorating 'Hooge Day' and the Durham Light Infantry, the local infantry regiment.
This in particular suggests the rest of the carriage is also on site somewhere, this could just be the forward wheels though (there's a lot of stuff in storage);
"Thank you for your recent e-mail and interest in the German field gun. I can assure you it is a real item and that it is a 150mm 1918 Krupp PM18 Kanone. It was captured and later placed on display in a park in Esholt in Yorkshire, later being tipped into the local sewage works filter beds (around 1925). It was discovered in August 1981 during reconstruction works at the works, recovered and later presented to Beamish by the Yorkshire Water Authority. It was restored and placed on display in the park on 9th August 1987, Hooge Day (locally significant to the DLI). Unfortunately over the years the elements have been unkind to the wheels in particular (though the supporting carriage, which is just around the corner, has faired very much better). We have recently been talking to a number of potential sponsors regarding restoration of the wheels (seriously expensive) and cleaning and painting the gun and carriage. This is very much dependent on the good will of others and may be regarded as 'in hand'.
I hope this answers your query and reassures you that the gun is cared for. I for one would very much like to tow it behind a locally owned 'colonial' traction engine used in the Boer War not quite appropriate but a good indication of the work these engines did.
Now I know what it is i'll do a photo walkaround when i'm up there next week - it's probably the WW1 artillery piece I see most often (Beamish is about three hours drive from where I live, but have family in the area so always go in when i'm visiting them). Fantastic collection there, they have a replica 1913 Daimler CC double deck bus which is of course very similar to the 'Old Bill' busses. Even gets fitted with proper solid tyred wheels in the summer season. Also have a horse drawn water cart that could be a WW1 vehicle, and plenty of other items of interest
Ralph is , of course, correct in his assertion. The only cosmetic difference between the WW1 version and his drawings are the added hard rubber to the wheels and the absence of brakeman's position( seat ) at the rohrwagen rear.
As an adendum, The Hooge Crater battles of July 1915 predate the introduction of this weapon by almost two years. Obviously, it's "capture" took place much later; perhaps after the armistice and subsequent German withdrawal.
As described in a previous post, the only connection to Hooge Day is that that is the date in 1987 when it was unveiled at the museum - the museum has an Edwardian setting so was given an appropriate display plaque