REBS Demonstration by Bob Shimon – San Jose Juniper

On August 27, 2019, Bob Shimon performed a demonstration for the members of the Redwood Empire Bonsai Society (REBS) on a San Jose juniper (Juniperus chinensis ‘San Jose’. Bob recently purchased the San Jose juniper from the member sales area at the August 24 and 25 REBS annual bonsai show. He said the San Jose juniper had character and interest as bonsai material for his demonstration. Some of the factors lending to character included: deadwood at the base of the trunk; a large base at the trunk; movement in the trunk; no or minimal taper in the trunk suitable for a bunjin or literati style bonsai; foliage concentrated at the top.

One of the first things to do when purchasing or beginning to work with bonsai material is to scratch away the surface soil from the base of the trunk to expose the root structure. A few inches is sufficient to observe the flaring of the trunk base. Bob saw a bunjin style bonsai within the material. He would proceed to cut and remove small interior branches. He would also remove unwanted branches and any dead branches. He said the main purpose of the demonstration material was to establish branch structure. There were two main trunks; one had to be removed as it was competing with the other and in conflict with the intended design. Bob used a sharp hand saw and removed the smaller of the two branches. What remained was a fairly long, curving branch with its foliage near the top.

Bod identified a number of smaller secondary branches that he would jin. Jin is Japanese for deadwood feature for a branch. Shari is also Japanese for a deadwood feature along the trunk of the tree. Both deadwood features are seen in nature and add to the character and age of the bonsai. Where branches were removed, Bob created jins. The jin is made from a short stub of the cut branch. A long jin is not true to nature. The best time of the season to work on creating jins and shari is when the tree sap is present.

Bob discussed a little about the horticulture for bonsai. Most bonsai require the outdoors. Exceptions are tropical and sub-tropical plants. Bonsai soil for junipers or conifers is on the dry side; usually one third pumice, one third lava rock and one third Akadama (a fired clay imported from Japan). Redwoods and deciduous require more moisture and use more Akadama. Fertilizers are required for bonsai since the soil mix for bonsai is inorganic. A common fertilizer schedule is any 10-10-10 fertilizer during the growing season and 0-5-5 during the winter months.

Bob said wiring is critical for bonsai. Learning how to wire properly is something that everyone must accomplish in order to work on bonsai. Copper wire is normally used with conifers, whereas aluminum wire is used on deciduous trees. Ivan Lukrich, the senior instructor at REBS, assisted in wiring of the demonstration tree. Ivan, who also teaches the beginners workshops, said REBS uses aluminum wire in the beginners’ workshops since it is easier to work with, can be removed and reused if needed.

Ivan proceeded to wire the San Jose juniper. The copper wire will require removal once it begins to indent the branches. The branches will grow larger but the copper wire will not, thus cause wire to cut into the bark making ugly wire cuts. He said observe the wire from time to time and ensure it does not cut into the bark.

Bob estimated the San Jose juniper to be about 20 years old. He recommended repotting with a bonsai soil mix next winter. He would use the same nursery pot but cut the pot in half to accommodate shortening the roots.

When the demonstration was finished, the San Jose juniper was raffled off to the members in attendance. Becky and David Jackson won the demonstration tree.

Bob Shimon, Becky and David Jackson with demo bonsai tree

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