Matson Navigation Co.’s “Christmas Tree Ship” — the MV Manoa — arrived in Honolulu Harbor early Sunday morning with 70 refrigerated containers full of trees and wreaths, and only six of them were held up because of hitchhiking slugs and yellow jacket wasps.

The relatively low number of pests means the latest arrival of Christmas trees will hit stores quickly and get into shoppers’ hands faster this year.

“This year’s shipment’s been pretty clean,” state plant quarantine inspector Glenn Sakamoto said Sunday as he inspected the arriving trees for invasive species.

Each Matson container can hold 200 to 500 Christmas trees and dozens of wreaths, said Kammy Chun, Matson’s manager for industrial engineering.

The slugs that were discovered Sunday at Matson’s Pier 52 will be inspected today to see whether they belong to a species that currently exists in Hawaii — just like the slugs that were found on two Christmas tree shipments last week, Sakamoto said.

Christmas tree wholesalers in Oregon and Washington have been doing a better job of catching critters on the mainland by putting out snail and slug pellets and by shaking trees before they’re packed for shipment to Hawaii, Sakamoto said.

On Sunday, one container full of Christmas trees was delayed for further inspection and possible treatment because it did not have paperwork showing that every tree had been shaken on the mainland, Sakamoto said.

Containers that carry pests foreign to Hawaii have to be sent back to the mainland — at the shipper’s expense — or more cheaply steam-treated in Honolulu, also at the cost of the shipper, Sakamoto said.

State agriculture officials estimated last week that 120,000 Christmas trees will arrive this year via Matson Navigation Co. and Horizon Lines. About 140,000 Christmas trees arrived last year.

Each Christmas, Matson designates one of its biggest loads of Christmas trees as its annual “Christmas Tree Ship.”