STONE PARSLEY

Sison amomum

Carrot Family [Apiaceae]

month8jul month8july month8aug

status
statusZcasual
 
flower
flower8white
 
inner
inner8cream
 
morph
morph8actino
 
petals
petalsZ5
 
type
typeZumbel
sparse
stem
stem8round
 
stem
stem8ribbed
slight
smell
smell8petrol
petrol
toxicity
toxicityZmedium
 
sex
sexZbisexual
 

Photo: (CC by 2.0) Geoff Toone
Grows tall, up to 1m high and has very thin (for its height) solid stems which branch profusely.


7th Aug 2019, Brookmans Park, South Hertfordshire. Photo: (CC by 2.0) Mike Adams
The main stem zig-zags slightly at each branch, of which there are many. The largest objects on this plant (apart from the longish branches) are the leaves by a long shot. The leaves are short narrow lanceolate near the top. Nearer the bottom of the plant the leaves are much larger (3 to 6cm long), pinnate with between 2 to 5 pairs of leaflets (sometimes pinnatifid - meaning with shallow lobes) with broad lanceolate leaflets with slight teeth nearer the bottom - but these leaves soon wither.


7th Aug 2019, Brookmans Park, South Hertfordshire. Photo: (CC by 2.0) Mike Adams
Nearer the top of the plant most leaves are linear but in very shortly but simply-pinnate form with just 1 to 2 pairs of these leaves. These leaves are on a short, sheathing petiole.


7th Aug 2019, Brookmans Park, South Hertfordshire. Photo: (CC by 2.0) Mike Adams
Some sparse umbels near the top are compound, with between 3 to 6 smooth rays up to 3cm long but usually with one longer than the rest. The stalk these umbels are attached to is longer than the rays. The bracts immediately below each umbel number 2 to 4 and linear-lanceolate or subulate (slender and tapering to a point).

The bracteoles just beneath the flowers also number 2 to 4 and are usually ovate-lanceolate.



7th Aug 2019, Brookmans Park, South Hertfordshire. Photo: (CC by 2.0) Mike Adams
The flowers (which are very small - just about 2mm across, are not zygomorphic but actinomorphic with 5 white petals with have smooth nicks at the tip) are in very sparse umbels on the many branches almost all the way up the stem. The flowers are without sepals and have styles with an enlarged base forming the stylopodium. The fruits (which here are green and still developing) will be about 3mm when ripe, almost without hairs and only slightly flattened laterally. The styles on top of the stylopodium are very short, only about half as long as is the stubbily short stylopodium and have a very stubbily short stigma atop.


7th Aug 2019, Brookmans Park, South Hertfordshire. Photo: (CC by 2.0) Mike Adams
Here is the root and stem of it.


7th Aug 2019, Brookmans Park, South Hertfordshire. Photo: (CC by 2.0) Mike Adams
Nearer the bottom of the plant the leaves are much larger (3 to 6cm long), pinnate with between 2 to 5 pairs of leaflets (sometimes pinnatifid - meaning with shallow lobes) with broad lanceolate leaflets with slight teeth nearer the bottom - but these leaves soon wither.

The sheaths (which hardly have sheaths) just below the junctions with their lobed and pinnate leaves. The leaves can turn a wine-purple colour before they drop off.



7th Aug 2019, Brookmans Park, South Hertfordshire. Photo: (CC by 2.0) Mike Adams
Two junctions of stems branching off near the bottom of the plant and the sheaths just below the junctions with their pinnate leaves. The stems are just slightly grooved or striated.


2nd May 2020, Brookmans Park, South Hertfordshire. Photo: (CC by 2.0) Mike Adams
Earlier in the year... A small turnip-like root with many leaf-stalks coming either straight from the tap-root, or branching off from the growing main stem(s?). Each leaf has between 2 to 5 leaflets.


2nd May 2020, Brookmans Park, South Hertfordshire. Photo: (CC by 2.0) Mike Adams
Earlier in the year... One leaf; this one has 3 leaflet pairs and a terminal leaflet (it can have between 2 and 5 leaflet pairs). They are cut in places to about half-way, each leaflet between 3 to 6cm long, and with many more much shallower cuts; all rounded-tipped.


2nd May 2020, Brookmans Park, South Hertfordshire. Photo: (CC by 2.0) Mike Adams
Earlier in the year... Several new plants developing, only the basal leaves evident yet.


5th Aug 2008, Fernhill Cottage, Newchurch, IOW. Photo: (CC by 2.0) Hilary Higgins
The pinnate leaves near ground-level. The teeth are also toothed.


2nd Aug 2008, Brighstone, IOW. Photo: (CC by 2.0) Geoff Toone


2nd Aug 2008, Brighstone, IOW. Photo: (CC by 2.0) Geoff Toone


2nd Aug 2008, Brighstone, IOW. Photo: (CC by 2.0) Geoff Toone
The leaves on the stem at mid-height are slightly less linear than those near the summit of the plant. All the leaves have a short but acute mucronate point at their tips.


Easily mistaken for : Corn Parsley (Petroselinum segetum), which, despite its botanical name, does not smell like petrol, but instead to Parsley. No relation to : Stone Bramble (Rubus saxatilis), Stone Pine (Pinus pinea), nor to any Stonecrops such as Biting Stonecrop (Sedum acre), nor Stoneworts such as Common Stonewort (Chara vulgaris). Nor indeed to any Parsley-Piert (Aphanes arvensis) [plants with similar names belonging to differing families].

But it is related to the following: Greater Bur-parsley (Turgenia latifolia), Upright Hedge-Parsley (Torilis japonica), Milk-parsley (Thyselium palustre), Parsley Water-Dropwort (Oenanthe lachenalii), Small Bur-parsley (Caucalis platycarpos), Cow Parsley (Anthriscus sylvestris), Fools Parsley (Aethusa cynapium) which are all Umbellifers.

According to one of the contributors, Mike Adams, this plant is exceedingly invasive in his garden.

There is only one umbellifer in the Sison genus, this one! Stone Parsley smells similar to petrol or to nutmeg and looks remarkably like Corn Parsley (Petroselinum segetum) but that smells of parsley (when either stem or fruits are crushed). However, Corn Parsley has pinnate lower leaves often containing many more paired leaflets (4 to 12) than just the 2 to 5 of Stone Parsley. The leaflets are also closer together on Corn Parsley. Corn Parsley is also a more glaucous-green than the brighter green of Stone Parsley.

It is to be found on river-banks, hedge-banks, or brackish grassland, especialy on lime soils. It is found mainly in South Yorkshire and East Anglia and scattered anywhere in a triangle from the tip of Cornwall to Hull and south-eastwards to Kent, with a patch in North Wales.


  Sison amomum  ⇐ Global Aspect ⇒ Apiaceae  

Distribution
 family8Carrot family8Apiaceae
 BSBI maps
genus8Sison
Sison
(Stone Parsley)

STONE PARSLEY

Sison amomum

Carrot Family [Apiaceae]